Hi, thanks again. I tried as you wrote but I cannot hear my voice, just a constand, uniform hiss. The same happened with these custom settings: Sample rate (Hz)                : 48000 Gain                            : Medium Sleep duration (s)              : 5 Recording duration (s)          : 5 Filter                          : - Trigger type                    : Amplitude Threshold setting               : -68 dB, -100 dB However, at -32 dB I get only tiny empty files (0 seconds length before expansion, like the first I uploaded). There is no difference in the "amount" of hiss or file size between -68 dB and -100 dB (as in the default setting) and file lenght is 5 seconds. Do you think it was caused by the prolonged exposure to high temperatures (abient temperature during the day may reach 40 Celsius, appartently higher for device and its case). This summer was rather hard for some of my devices. I cannot see any signs of defromation or corossion. This specific device was set ca 7m above the sea and had some salt on the case and inside, but other devices have similar problems with no such treatment. Could it be detachement of the microphone. Is there a way to fix this? Pangeos

Thanks a lot for the reply. The sleep and recording periods were always the same (in hundreds of recordings), with no problem. After the problem appeared, bats were seen flying at night in front of the AM, but they were not recorded . Rubbing my hands (just now) resulted in tiny files with no sound, as the one posted before. Then I turned the switch to default but nothing was recorded when I spoke to it at the suggested distance - see file uploaded here. What do you think?

This a typical example of the files produced