I am trying to set up a 7-day continuous recording at a 48kHz sample rate. However, when using 1.5V rechargeable lithium-ion batteries, I am encountering severe SD card read/write errors. This issue is highly prevalent among a batch of 30 newly purchased devices. Under the exact same configuration, about 1 in 6 devices experiences this issue, and the behavior is becoming increasingly unpredictable.

Hardware Tested:

• SD Cards: Kingston Canvas Select Plus (256GB); SanDisk High Endurance (32GB, 64GB, 128GB).

• Batteries: 1.5V Constant-Voltage Li-ion: iNeno AA (3700mWh), Sidande AA (3600mWh); Panasonic NiMH rechargeable (2300mWh); Standard Alkaline batteries.

Observed Issues:

1. Battery Performance Discrepancies:

We installed 31 audiomoths in the field. Upon collection after 2 weeks out, all audiomoths have stopped recording before collection - they recorded for a maximum of 5 days. We used 3 previously used Energizer Ultimate Lithium AA 1.5V Batteries but all had their voltage checked before deployment to ensure a voltage of 1.6+V (showing ">4.9V" in Audiomoth Configuration App). We used SanDisk Extreme 128GB SD Cards also previously used and formatted in exFAT. Audiomoths had Firmware 1.12.1.

All audiomoths had the single green flashing light when switched to custom mode when deployed (configuration text attached).

We created the Summaries via Audiomoth Configuration App for all the SD Cards. This showed that the first (and most of) error was "SD Card Write Error". The audiomoths stopped recording anything after doing 5 1KB recordings and the average voltage of the last recording was 3.7V.

Summaries also showed that battery voltage dropped…

I would like to share some findings on the energy consumption of different microSD cards, inspired by earlier posts by Javier Seoane and Laura Molles (https://www.openacousticdevices.info/group/support-forum/discussion/923f8974-c6a1-4283-a89c-8d9c71b877af).

Since SD‑card write current is one of the main contributors to AudioMoth power consumption, choosing an efficient card can substantially extend deployment time.

Motivated by a limited budget and the rising prices of memory cards, I recently decided to acquire and test several lower‑cost, slower cards. I used a power meter capable of measuring true‑RMS voltage and current and integrating them into mAh. All measurements were performed on AudioMoths running firmware 1.11.1, using default settings (55 s recording, 5 s sleep) at 48 kHz.

All cards were purchased in 2026. I found no variation between samples of the same model.

I deployed the cards in the field and compared the voltage reported in the metadata with the discharge curve of the AA alkaline batteries used. The results matched…

I ran into an issue during one of my AudioMoth deployments where the recorder did not make any recordings.

The AudioMoth was configured in CUSTOM mode with a recording schedule from 18:00 to 06:00. The same AudioMoth and the same schedule had worked correctly during the previous deployment week. I did not change the CUSTOM switch position between deployments.

For this deployment, I used a new SanDisk Outdoors FHD 64 GB microSD card, the same type of card that I had successfully used before. The batteries were also replaced before deployment.

After retrieving the AudioMoth, the SD card was completely empty and contained no WAV files or summary files. I also observed a red and green LED on the device, which seems similar to other reported cases of recording failure or SD card write errors.

Based on the LED behaviour and the empty SD card, I suspect this may have…

Hello. I have a new AudioMoth that I am trialling before putting out in the field. I am using a SanDisk Extreme and Duracell Optimum batteries. Each time I start recording (switching to Custom), I get the device recording and saving files and then it simply stops recording. Both LEDs flash suggesting a recording error. I have formatted the SD Card and also run a write/read test on it (all good). The length of time before stopping seems to be between 1 and 6 hours.

I've attached the config file, the recording file summary from the last test, and the SD card RW results.

Any suggestions would be greatly appreciated.

Thank you,

Martin

Hello, I purchased two AudioMoth 1.2.0 units and both are experiencing software issues. When I retrieve the SD card, the red and green lights are almost always flashing simultaneously. Occasionally, the card contains unrecognized files and that it needs to be formatted. I haven’t been able to open these files on Windows or Mac, resulting in data loss.

At other times, the device manages to record files, but the red and green lights continue to flash regardless. Upon reviewing the content, I find duplicate recordings and files with filenames that do not correspond to the correct date and time.

I am based in Bolivia, and it is very difficult for me to ship the equipment back to the United States. Is there a way to remotely update the devices to a better software version?

I would like to share some results as a continuation of an earlier post on energy consumption of SD cards at https://www.openacousticdevices.info/support/sd-card-support/u1-vs-u3-microsd-cards-field-data-contradicts-recommendations?origin=notification

We conduct an indoor experiment using Audiomoths with firmware version 1.11.0 in a recording window of 180 minutes. The sample rate is set at 48kHz, and the gain is set at medium. We enable sleep/record cyclic recording. We use daily folders for the generated WAV files. We combined two sets of different recordings and sleep durations with different SD cards and battery models to assess the effect of sleep durations, and the type of card and battery. These are:

Alcaline vs lithium

Lithium batteries do not extend the operating time beyond what alkaline batteries did when the recording schedule was intensive (recording each minute during the 180-minute window). Compare BAU2 vs BAU1.

Recording scheme

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?

Hello Open Acoustic Devices,

We ran into an issue during one of our 2-week-long deployments where the Audiomoth stopped recording after 2 days despite having enough battery and SD card storage to last 2 weeks. The Audiomoth configuration was at a sampling rate of 192kHz, a 5min ON 5min OFF sleep/cycle scheme for a 24hr recording period.

It was placed within an Audiomoth dev case and the battery connections have been checked. We are using 3 Paleblue D cell rechargeable batteries. And the microSD card is a 256GB Sandisk Extreme UHS Speed Class 3 (U3) microSDHC card. The SD card was reformatted to exFAT before being used.

Below I will attach the SUMMARY.CSV and a picture of the Audiomoth inside the dev case. The Audiomoth was recording (flashing red) at time of deployment and we recovered it a week later under an error mode (green and red flashing). When using…

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…

Hi, after formatting my SD-card on my Mac, my HydroMoth doesn't read it anymore (flashing both green and red at the same time). It does still read other SD-cards, so no device problem. How can I make my SD-card work again for the HydroMoth?

Hi everyone,

I got all my recordings with this kind of noise (in picture) on a Hydromoth Firware Basic 1.11.0. We used SD card SanDisk Extreme 64 Go.

Could it be the SD card when is writing? Do you have any recommandations?

Thanks,

Hi,

I recently bought 2 AudioMoths and 2 SanDisk Extreme 64GB Micro SD cards. One AudioMoth has configured with no problem at all and is working as expected. The other AudioMoth, upon configuration, blinks green, but when the scheduled recording starts while in CUSTOM mode, or when I attempt to record in DEFAULT, there are 4 long green and red flashes, before intermittently flashing green and red. No recordings are made.

The diagnostics page here (https://www.openacousticdevices.info/led-guide#:~:text=Both%20lights%20flashing%20(100ms)%20on,a%20recording%20being%20cut%20short.) suggested that, when this happens in either CUSTOM or DEFAULT, it is an ´SD card write error or low battery´.

I have changed all batteries to new and functioning batteries and this has not resolved the issue. I have also:

• Tried the SD card in the other AudioMoth, where the other AudioMoth worked without any problems, suggesting to me the SD card is not defective

• Tried a functioning SD card in the AudioMoth which…