The last couple weeks me and my project partner have tried to record bat calls at night using three Audio Moths, utilizing a scheduled recording time frame. Because of the bat call frequencies, we use the 192 kHz setting. Unfortunately, after seven days of recording, only five days were properly recorded on two of the Audio Moths. During the last two days, empty 1kB files were created (though they were on the correct starting time), while there was still storage left on the SD cards and the battery volt was still high enough after the test. We have tried to format our SD cards, use different batteries and check our settings. Our last test this week with one of the Audio Moths resulted in an empty file being created each day. We have purchased stronger batteries (Energizer Ultimate FR6 lithium 3000 mAh 1.5 V) and hope this might solve the issue. Does anyone have any ideas of what the cause might be and/or suggestions on how to solve it? Many thanks in advance.

Lucas