Hi there, I have been using my audiomoth successfully to record bat calls from sunset to sunrise here in the UK. The audiomoth is configured to record for 15 seconds periods followed by a 5 second pause. All was going well until recently. Visually scanning the wav files using kaleidoscope after a nights recording reveal that the files are getting progressively shorter. Although configured to 15 seconds, last night the first file (at around sunset) recorded for 6 seconds and gradually the periods reducing to zero seconds by about 5 am. The same thing happened the night before, the actual recording period started at 15 seconds (at sunset) but reduced during the night to a recording period of less than a second. Has anybody got any thoughts what the problem might be? I have tried reconfiguring the AM. Perhaps I should re load the firmware?
Best wishes, Richard
Glad we got to the bottom of it. Andy
Thanks Andy. I think that's it. Just re-visited the page on what the flashing lights mean. I thought that the more red flashes when switching to USB/OFF meant a battery with lots of charge. This is the case with alkaline batteries - but not with NiMH ! Thanks, a slightly embarrassed Richard
Hi Richard, That's good to know. If that's the case it's most probably the battery. In the WAV comments in the shorter recordings it should state the reason for stopping as low battery voltage.
The 0KB files result when the AudioMoth has opened a file but was not able to close it. This normally happens due to the battery running down during a recording. The 'Enable low-voltage cut-off' option attempts to prevent this by stopping recordings early due to the the low voltage but it is still possible for the write to fail at low voltages depending on the type of SD card.
Hi Andy, Thanks for quick response. I download the previous nights recordings on to my laptop and delete them from the 64GB Sandisk sd card by reformatting it before each nights recording. So it can't be a full SD card.
Hi Richard,
I have a feeling this could be an SD card issue. Are you deleting the files from the SD card each night? As SD cards fill they take longer to open and close files. It might be that your SD card is getting full and needs reformatting. Let us know if that fixes it, Andy