Hi, I have been recently trying to record bat ultrasound with Audiomoths v1.2.0 with firmware 1.8.1 installed. In recording sessions scheduled for two nights (i.e. starting at 19:35 and ending at 6:15 next morning) I got long periods with files recorded without the RIFF head (so, they are unreadable and I cannot expand them with the configuration app) with some sporadic files with erroneous RIFF chunk size, which I cannot expand with the app, but have data that I can visualize in a WAV editor, and then periods when the audio files where correctly recorded and could be read. For example, one night I got this list of erroneous files:
20230614_193500T.WAV - RIFF chunk size does not match file size.
20230614_193516T.WAV - Could not find RIFF chunk ID.
20230614_193532T.WAV - Could not find RIFF chunk ID.
...... some 790 more erroneous files until
20230614_230036T.WAV - Could not find RIFF chunk ID.
20230614_230020T.WAV - Could not find RIFF chunk ID.
20230614_230004T.WAV - Could not find RIFF chunk ID.
and then normally recorded files from 23:49 up to 02:33:
after that, I got a new long period with erroneous files:
20230615_023340T.WAV - Could not find RIFF chunk ID.
20230615_023356T.WAV - Could not find RIFF chunk ID.
20230615_055205T.WAV - Could not find RIFF chunk ID.
20230615_055149T.WAV - Could not find RIFF chunk ID.
Up to the end of the recording schedule at 06:15
And then no good files either recorded until 22:45 next evening (the recording schedule started at 19:35)
.... and recorded good files up to the end of the schedule at 6:15
So, any idea of what was going on?
The recordings were being done in a desert area in northern Mexico, in mid June, and the temperature was very high (35.3 °C according to the first Audiomoth recording at 19:35). Could the ambient temperature affect the functioning of the Audiomoth?
Thanks for the attention,
Toni Guillén, Instituto de Ecología AC, Xalapa, Veracruz, México