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Time displaying incorrectly.

I'm trying to set up my AudioMoth, but it doesn't display the correct time and I can't manually set it. The time now is 17.29, but the app says it's 01:48 UTC +1

I have installed Chime which does show the correct time, but I can't see where to enable Chime in the configuration.

Can someone please advise?

52 Views
Alex Rogers
Alex Rogers
2 days ago

Hi,


The Config App is showing you the current time on the AudioMoth that is plugged in. This one has been powered for 44 minutes and 36 seconds, and you are in timezone UTC+1, so the time is appearing as 01:44:36 01/01/1970 UTC+1. When you press 'Configure AudioMoth' it will send the current configuration to the AudioMoth and also set the time. You will see the displayed time will update to the current time.

If you remove the batteries at any time, the configuration will still be saved, but the time will be lost. If you switch to CUSTOM without having set the time, the AudioMoth will show a constant red LED and a flashing green LED whilst it listens for the acoustic chime.


There are some quick-start guides here: https://www.openacousticdevices.info/setup-guide Alex

Edited
Machteld Verzijden
Machteld Verzijden

Error when updating to latest software + recordings faulty when used with older version

I recently bought 10 audiomoths, and 9 of them work perfectly, but there is one unit that is not able to update to the latest software.

I get an error message, see attached image.


When I tested it using the version of software that it came with (1.10.1), I can configure it, it will record at the right times, but the recordings are faulty (it almost sounds like the soundfiles are backwards).


Is there any options in the AudioMoth Flash App that I can try to reinstall the audiomoth?


Thanks in advance for any advice,

Machteld


66 Views
Alex Rogers
Alex Rogers
2 days ago

Hi Machteld,


I think this AudioMoth has a bad external SRAM chip. Can you share one of the WAV files. You will be able to flash it if you deselect 'Use USB HID flashing' in the Flash App menu. However, the sound will still be distorted. You would be able to use this device as an AudioMoth USB Microphone as that firmware does not use the external SRAM chip. However, if you contact the seller, they should replace it for you.


Alex


Use chime but keep sleeping and recording duration

Hi Everyone,

to just change battery and SD card in the field I'm trying to use the chime app to setup the time after those change. Yet, it seems that it overwrite the initial config.txt and thus I'm loosing my initial sleep and recording duration. Do you know if there is a way to combine Chime App to setup time and keep parameters of the custom config.txt already on the SD card?

Thanks!

197 Views

Hi Maxime, The chime does not change any of the settings on the AudioMoth - it only sets the time.

The AudioMoth does not read the CONFIG.TXT file - it is just an output summarising the settings.

When you switch to CUSTOM the AudioMoth will write a new CONFIG.TXT file with the configuration set the last time the Config App was used. Alex

I haven't used my Audiomoth since last autumn and wanted to deploy it again. I'm using the same PC as I used previously except that the operating system is now Windows 11 (previously 10). When I plug in the Audiomoth using the same USB cable I have always used, I get the solid green light but there is no information in the Device ID box in the Configuration App. (New batteries, functioning microSD tested in another device, slider set to USB/OFF). I tried multiple USB ports.


I tried the Flash App which says no Audiomoth found. I then followed the instructions to manually switch to serial flash mode. I got the dual flashing red/green LEDs which turned off when I put a paper clip across the appropriate pins, but no matter how many times I tried this the Audiomoth is not detected.


Please can you provide some advice? Maybe it's…


148 Views

Hi, Can you check the Device Manager to see if the AudioMoth is appearing as a USB device there. Double check that the USB cable is definately not a charging cable with no data lines. Alex

Alter firmware to accept digital I2S audio signal

Would it be possible to modify the Audiomoth firmware to accept a digital I2S audio signal instead of the analog signal from the onboard microphone handled by the internal ADC in the EFM32 chip.


It seems that the limitation in the audio quality of the Audiomoth device is related to either the signal path or the internal analog to digital converter wich is supposed to have 12-bit resolution but has a real resolution of roughly 8-9 bits and quite a bit of noise.


Maybe it would require a whole new firmware? Even if most of the audio settings in the firmware wouldn't work, it would be useful if the scheduling, highpass and lowpass filter, amplitude threshold and such worked.

344 Views

Q1

Is the Audiomoth firmware open source? Or how can we achieve a modified version supporting I2S digital audio signal input on the EFM32?


Q2

Is it correct that the Audiomoth 1.2 is running one or more low quality capacitors in the analog signal path? It seems so when studying the PCB.


Q3

Is the hardware layout available open source if I want to modify it to increase the audio quality of the device in the current layout.


Thank you!

Edited

reading audiomoth header data in R

I found this old R package:


but it seems it hasn't been updated in years.


I want to read header info from the wav file produced by audiomoth recording - does this have start and end battery life, for example? Or can I only read battery voltage when I plug into the Audiomoth configuration app? if these and other data are in the header, how would I go about opening that, preferably in R?

If I'm thinking about this all wrong, can someone point me down the correct path?

273 Views

Hi, The header files contain the battery voltage measured at the start of the recordings. It is also in the GUANNO metadata which is at the end of the recording. Both could be simply extracted in R by reading the start and end of the file as a text files. On Linux you can extract them from the command line:

You could also use the 'Summarise AudioMoth Files' tools in the Config App which will generate a CSV summary of the all the files in a directory or SD card, including all the header and GUANNO meta data.

The Config App uses the AudioMoth-Utils repository (https://github.com/OpenAcousticDevices/AudioMoth-Utils) to read and process WAV files. These are all Node.JS libraries. Alex

anonymous birder

I am starting a bird vocalization monitoring project with an Audiomoth, in Los Angeles and I'm looking for assistance with how to do the audio processing on my computer. Can someone help me find the right resources?


Thanks


joe

391 Views

Hi Joe,


For viewing AudioMoth recordings we'd recommend AudioMoth Play (https://play.openacousticdevices.info). You can apply filters and generate vidoes and audio clips. Many people use platforms such as Arbimon (https://arbimon.org) to store and analyse more extensive sets of recordings.


Similarly, BirdNet (https://birdnet.cornell.edu) is increasingly use for automatic AI analysis of bird song.


Alex


sunrise/sunset schedule + another period

Hello, I need to create a sunrise/sunset schedule but with an additional recording period around midday. Is that possible? If not, do you plan to implement it? Thank you very much.

322 Views
Alex Rogers
Alex Rogers
Nov 24, 2025

Hi, It's not possible at the moment. However, you can record from before sunrise to after sunset with the current settings. Alex

Chime app not available

Hi,


I tried to install Chime on my mobile and got this:


Is there a newer version available for Android?


Thanks,

Dana

255 Views
Alex Rogers
Alex Rogers
Nov 13, 2025

Hi Dana, Thanks for pointing this out. There's an update coming very soon anyway but we weren't aware of this issue. The browser version should work fine on your Android phone - follow the 'Browser' link. Alex



Record without time

Hi,

Can anyone tell me what i need to change that the moth will start recording immediately without any set time. (only recording period is set once - to limit the filesize) It could name the files like 1.WAV, 2.WAV or so. i dont need a timestamp and the setting of the time only complicates deployment. GPS only needs battery...

The next thing i'd like to know is why this device "looses" its firmware sometimes if the battery is disconnected for some time.


Thanks in advance

Phil

276 Views
Alex Rogers
Alex Rogers
Oct 31, 2025

Hi Phil,


If you switch to DEFAULT the AudioMoth will make a continuous recording with the current configured recording settings (gain and sample rate) without having to set the time.


If you use the GPS board with the AudioMoth, it will set the time from the GPS board when you switch to CUSTOM so you don't need to set the time then either.


The AudioMoth shouldn't lose its configuration or firmware. Both are stored persistently in flash memory. If you remove the battery however it will lose the time, so you will need to set the time with the Time App or smartphone app prior to recording.


Alex

Edited
Felix Häfele
Felix Häfele

MicroMoth sampling rate cap with GPS sync FW

Hi everyone,


when reading the documentation on Github I see that the sampling rate is capped at 192 kHz for use with the dedicated GPS sync FW (https://github.com/OpenAcousticDevices/Application-Notes/blob/master/Using_AudioMoth_GPS_Sync_to_Make_Synchronised_Recordings/Using_AudioMoth_GPS_Sync_to_Make_Synchronised_Recordings.pdf). When I look at the sample SETTINGS.txt (https://github.com/OpenAcousticDevices/Application-Notes/blob/master/Using_AudioMoth_GPS_Sync_to_Make_Synchronised_Recordings/SETTINGS.TXT) provided the parser seem to enforce 125 kHz. I am interested in recording bats and localizing them with synced MicroMoths and I was hoping to use a sampling rate of 384kHz. Is it not possible to sample that high when using the GPS hat?


Best wishes,

Felix

211 Views
Alex Rogers
Alex Rogers
Oct 31, 2025

Hi Felix,


The maximum sample rate for AudioMoth-GPS-Sync is 192kHz. I've updated the example file. The AudioMoth doesn't have time to do the necessary processing at 384kHz.


However, you can make synchronised GPS recordings with the standard firmware at 384kHz. The synchronisation is typically then only +/- 1 ms rather than +/- 1 us. The application note below describes this approach:



We have an update coming out in the next few months that might improve this to about +/- 0.1ms.


Alex


Edited

GPS data from Chime App

Hello,

When I use the Chime app to start an audiomoth recording, and select GPS in that app, does it save that GPS in the audio metadata?


I have taken to taking a photo and using exif, but if the data is in the wav somewhere that would be ace.


Thanks

222 Views
Alex Rogers
Alex Rogers
Oct 12, 2025

Yes, as Edwin says the GPS location is stored in the GUANO meta data which is added to the end of the WAV file. The AudioMoth Play app (https://play.openacousticdevices.info) can read and display this data.


You can also access it through the 'Summarise AudioMoth Files' option under the 'Process' menu in the Config App.

It is also easy to read directly in Linux or Mac.


Edited

Accessing SD-Card Data per USB?

Is it possible to modify the firmware so that the data stored on the SD card can be accessed via USB connection, instead of removing the card from AudioMoth and connecting it to a PC with a card reader?

474 Views
Patrick Spooner
Patrick Spooner
Oct 07, 2025

If the units can be permanently connected to a computer, we have a python script to record from many (>12) on one Linux PC, saving data directly to flac files. We use the audiomoth mic firmware so no sd card and usb powered.

Configuring the USB Microphone through USB commands

Hello,

Great work. I'm currently using the HydroMoth as well as 2 USB microphones for another project.

Everything is ok.

I wonder how it could be possible to configure the USB microphones using a simple HDI or another USB command.

Indeed, since there is no battery on this board the configuration cannot be permanent and each time the board is unplugged the configuration is lost.

Default configuration, 384 kHz, no filter, average gain is ok in most cases but if I want something special, it's not possible.


362 Views
Alex Rogers
Alex Rogers
Sep 28, 2025

Hi, The AudioMoth USB Microphone configuration is persistent even if the microphone is unplugged. It is stored in the flash of the microcontroller alongside the firmware. In most use cases, you can switch to USB/OFF and configure the microphone with the AudioMoth USB Microphone App. The settings are then retained whenever you unplug and plug-in the microphone again.

You can also configure the microphone from the command line using the app described in the application note below. This app allows the configuration to be changed when the microphone is in DEFAULT or CUSTOM mode and acting as a USB microphone. https://github.com/OpenAcousticDevices/Application-Notes/blob/master/Configuring_the_AudioMoth_USB_Microphone_from_the_Command_Line/Configuring_the_AudioMoth_USB_Microphone_from_the_Command_Line.pdf The application can list connected AudioMoth USB Microphones and then configure them individually or collectively:

You can even put the AudioMoth USB Microphone into bootloader mode and then use the Flash App to update the firmware without having to manually change the switch setting.

It requires firmware version 1.3.0 or later, as this creates an additional interface on the microphone that allows the configuration to be updated. The AudioMoth-Live-App uses this interface to adjust the device gain whilst the microphone is running.


The command line application can be built from the source code in the GitHub repository: https://github.com/OpenAcousticDevices/AudioMoth-USB-Microphone-Cmd There are also pre-built installers for all platforms here: https://github.com/OpenAcousticDevices/AudioMoth-USB-Microphone-Cmd/releases/tag/1.0.1 Let us know if you have any problems.

Alex

Edited
Katie Garwood
Katie Garwood

using the AudioMoth-EdgeImpulse repo

Hello, I was able to compile an edge impulse model and used the audiomoth-edgeimpulse repo to flash onto my audiomoth. it does appear to be working, I'm just confused about a few settings and how to interpret the results.


My main question is- Edge Impulse requires at least 2 classes to train an acoustic classifier. I have one class being my bird of interest, and my second class is "background noise" of either other birds in the area or just regular background noise. But I was unable to see where in the audiomoth firmware where you tell it which class to look for and "trigger" to store on. Is it triggering and storing the results for both classes? Or just the first class? I would prefer it to store only the class of interest. Based on the saved wav files im getting, it seems to be storing both, but I…


207 Views
Alex Rogers
Alex Rogers
Sep 10, 2025

These files only contain a header and no data. Check the WAV file header comments to see why. The ‘Sumarise AudioMoth Files’ option under the ‘Process’ menu in the Config App will generate a summary CSV file from the SD card.


It’s possible that the battery voltage is low. Also the SD card might be full. Always reformat before deployment, rather than deleting files.


Moth not being recognized by PCs

Hi, I have an AudioMoth and I haven't tried to use it since a year ago or so. It's less than two years old. I can't get it to be recognized by either of my Windows 11 computers. Power to the device occurs but nothing in the device manager. I have tried installing drivers from Silicon Labs to no success. It used to work with my old computer running a much older Windows OS. I'm thinking software got corrupted on the AudioMoth. Multiple cables, multiple computers, multiple drivers. Batteries removed. I give up. I can't see a reset switch anywhere on the AudioMoth device. I get a solid green light on the device so there's power but no life.

253 Views
Alex Rogers
Alex Rogers
Sep 04, 2025

Hi, I think it is unlikely to be the AudioMoth. Nearly all connection problems are the USB cable being a charging cable with no data lines or a Windows driver issue. What operating system are you using? Anything newer than Windows 7 shouldn't require a driver as it will use the default ones. Have you used an EasyLog data logger from Lascar Electronics on these computers? Their driver incorrectly claims the same USB PID and VID.


It's possible to put the AudioMoth back into serial bootloader mode so that the firmware can be reflashed. This uses a different USB protocol so likely still works if the standard one has a driver issue. Select 'Show Manual Switch Instuctions' under the menu in the Flash App. This will guide you to connect the two 'PROG' pins together whilst powering up the AudioMoth so that it starts in serial bootloader mode.


I think the cable or driver issue is more likely however. Alex




Rodrigo Oyanedel
Rodrigo Oyanedel

Recording at 24kHz sample rate

Hello, is there a way to record at 24kHz sample rate? I cannot see the option in the AudioMoth config, but I wonder if there is an alternative way to do so?


Thanks a lot!

Rod

150 Views
Alex Rogers
Alex Rogers
Aug 29, 2025

Hi, No, it's not possible to record at 24kHz on AudioMoth. You can record at 32 or 48 kHz and downsample the file in post-processing if necessary. Alex

GPS Hat Issues

Hello, I have been having issues with getting some GPS hats to get a fix.


I have successfully soldered some Audiomoths and GPS hats together, and they have been able to get a GPS fix from inside a lab room inside a building, far away from doors and windows. However, two other Audiomoth/GPS hat units have not been able to get a fix from the same location, even if close to doors and windows. I have been using a SETTINGS.TXT file that the functional units have been able to get a fix with. I can provide the file if it would be helpful to see it.


Both Audiomoths function properly with Audiomoth-Firmware-Basic and can record files using a configuration from the Config App that does not use the GPS hat. When I soldered the functioning Audiomoth/GPS hat units together, I used a multimeter to measure their resistances and connections, and…


181 Views

I have purchased two audio moths and 2 GPS Hats. The audio moths are working properly but the GPS hats are not outing any GPS Information as they should. I had them both professionally soldered to the audio moth. Neither of them are working. Here is a copy of the log. There is no config log or anything.


Aditya Krishna
Aditya Krishna

488-byte files

Hello Open Acoustic Devices,


I wanted to get some clarification on a problem we have observed when using the Audiomoth to collect recordings in an outdoor natural area. We sample at 192kHz, 300s/300s record/sleep cycle, and equip our Audiomoths with 6 or 9 AA rechargeable batteries.


We have noticed that our Audiomoth sometimes changes mode during deployments and produces "empty" 488-byte files that do not contain data and are short. It goes into this mode and might generate 100s of such files and then comes back to generating normal files.


I am attaching a couple screenshots from previous deployments of the file explorer view alongside an exiftool-based readout of the file metadata. You can see the normal files will be generated before and after the error "488-byte" files. These problems persist in the same manner even to this day with new firmware and new Audiomoths.


I can generate a SUMMARY.CSV…


181 Views
Aditya Krishna
Aditya Krishna
Aug 25, 2025

I see, thank you for the clarity! We have purchased silica gell packets and will use them.


And thanks for the quick responses as well!

Carsten Wartmann
Carsten Wartmann

Moth Play improvements

Hi,

new to the game. I was always curious to record birds and bats here but never got further than Bird.net on my phone.


So I bought an AudioMoth :) Got some nice recordings from "our" bats here yesterday night.


Moth Play is a nice browser-based app; however, I see some possible improvements:


  • Keyboard Navigation in File-List: Maybe CTRL-Cursor Up/Down to goto the next/prev file and load it. Nice for checking through the recordings (now it is mouse only?)

  • Save as: Saves a WAV playable on any computer JUST as it is played inside Moth Play for sharing. Should ask for a File-Name and remember its folder All the best, Carsten


94 Views
Elmar Werling
Elmar Werling

Synchronizing Recordings from Multiple AudioMoth Devices

I need to synchronize the recordings of several AudioMoth devices with microsecond precision. I attempted to do this by turning the devices on approximately simultaneously in default mode and recording a reference signal both at the beginning (within a few seconds) and at the end of the recording, just before shutting the devices down.

Unfortunately, the signal at the beginning and the end of the recording is sometimes not captured.


I have three questions regarding this:

  1. How long does it take for an AudioMoth device to start recording after being powered on (in seconds or milliseconds)?

  2. At what intervals are recordings saved to memory (e.g., every minute, every 15 minutes)?

  3. Are any recordings lost or skipped during the saving process, or is all data continuously stored?


170 Views
Alex Rogers
Alex Rogers
Aug 07, 2025

Hi Elmar, Depending on the contents of the SD card it can take up to five seconds to open the file and start recording. In normal use, the AudioMoth firmware tracks this duration and adjusts it's preparation time so that the recording always starts at the required time. If you set the clock on the AudioMoth immediately before recording, and use a scheduled start time, then all the AudioMoth recordings will start at the required time. The realtime -clock drift can be up to +/- 80ms per hour so you will need to allow for that uncertainty. If you are recording outside you can use the GPS board and the AudioMoth-GPS-Sync firmware. This runs the GPS continuously during recordings and provides software to automatically synchronised recordings to +/- 1us. https://github.com/OpenAcousticDevices/Application-Notes/blob/master/Measuring_the_Accuracy_of_AudioMoth_GPS_Synchronisation/Measuring_the_Accuracy_of_AudioMoth_GPS_Synchronisation.pdf This firmware uses the pulse-per-second (PPS) output of the GPS throughout the recording. You probably won't be quite as accurate if you only synchronise the recordings at the start and end as the internal 48 MHz clock will drift slightly over the course of the recording due to the temperature fluctuations. If the temperature is consistent you'll get the best results. Also, 1 us is a lot less than the inter-sample period (22 us at 48 kHz), so you will need to be quite careful interpolating the recordings when you try to correlate the recording with the reference signal. We've done this in the past by interpolating the zero crossing times of the waveform.


The recording schedule is determined by whatever you set in the Config App. Data is written to the SD card continuously in 32 KB chunks during the recording. At 48 kHz this corresponds to 341 ms. Alex

Accuracy of sunrise/sunset times

Hi, I'm using the civil sunset to civil dawn setting for my nocturnal migrating bird recordings, based on lat/long and using a rounding of 1 minute. My recordings start about 3 minutes later than the scientific sunrise/sunset tables I used in the past. Is this normal variation for the AudioMoth, or is there something else I can do to have an exact match with the times calculated in the tables? Thanks for your assistance!

John

87 Views
j.f.kearney
Aug 03, 2025

Hi Alex, yes, they all use lat./long. Your reply sparked me to compare with the calculations of the National Research Council of Canada calculator for Sunrise/Sunset, which should be the most accurate for my location. It gave me a time within 2 minutes of the AudioMoth. Perhaps changing my rounding from 1 to 0 would bring me even closer. In any case, I can live with a 2-minute difference.

Useful feature.

I wonder if it is possible for the developers to add a feature to the firmware whereby configuration files could be made time and date specific?

In other words during daylight hours a configuration optimized for birds and mammals could be loaded, and during the hours of darkness a configuration optimized for the ultrasonic detection of bats loaded? or alternate between night time ultrasonic and normal spectrum on different days.

This would be a powerful feature maximizing the amount of data a single device could gather in an unattended deployment.

91 Views
bobmcnair01
Aug 04, 2025

Many Thanks Alex, that will be VERY useful .


How to have the audiomoth only record when triggered

Hello, i have the audiomoth recording continuously 20s on and 5s off but I want to get it to only record when the amplitude and frequency are correct. Please see my config file below. Any suggestions on changes I need to make please?



141 Views
craigsellwood
Jul 11, 2025

Ive tested by very scientifically jangling my keys at it. It seems to have worked, thank you.

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