I have changed the sd-cards, e.g. with the slower and also cheaper SanDisk Ultra class 10 or other similar cards I had regularly this recording problems. With the faster SanDisk Extreme XC1 V30 A1 U3 I never had this problems.

Update: With two devices I had the problem, that 133 out of 6143 files were empty (0kb). This problem occured identicly with two devices, which had the same settings. Suprisingly, I cannot generate a new order or file on the SD-card, if I try, the explorer crashes. Anyone an idea, what could be the problem?

Update on test: The flashing of the red LED for two days indicated that the three units were in recording mode.On the third day, a green LED on one unit was blinking continuously, the others were still correctly red. I checked the SD card and found that two devices had recorded absolut correctly, but the third SD card could not be read and needed to be formatted. I couldn't find out if the error was caused by the device or if it had something to do with the SD card, over two days the device also showed that it was recording. I will remove this SD card at least for use with Audiomoth.

After Device ID : 248D9B045CC5C964 Firmware : AudioMoth-Firmware-Basic (1.4.4) Time zone : UTC Sample rate (Hz) : 48000 Gain : High Sleep duration (s) : 5 Recording duration (s) : 55 Active recording periods : 2 Recording period 1 : 00:00 - 08:00 (UTC) Recording period 2 : 20:00 - 24:00 (UTC) Earliest recording time : 2020-09-04 00:00:00 (UTC) Latest recording time : 2020-09-13 00:00:00 (UTC) Filter : - Amplitude threshold : - Enable LED : true Enable low-voltage cutoff : false Enable battery level indication : true ------------------------------------------------------------------------------------- I deposited the device on 03.09. in the afternoon. The first recording was on 04.09. at 07:10 UTC. Time of the CONFIG file is 07:11 UTC. I don't have the other config file anymore, the start was correct on the other device but after 2 days the recording ended. Settings were the same. Currently I have a test with three devices running at home over several days. I will report on the results.

I run with the version 1.3.6 and firmware version 1.4.4

The test at home with the settings recording time 00:00 - 24:00 (UTC) and recording duration (s) : 360; (sleep duration 5 s) resulted in the first recording at 5:40 UTC although I started the device already yesterday evening. After interrupting the recording to check the SD card the recording starts immediately. I can't figure it out but the device is no longer reliable. Is there a way to flash back the firmware to the previous version?

I have now a test running at home, we will see if it stops again.

When I first encountered the problem, I removed exactly this checkmark when I reconfigured, but the problem still exists. Recording devices one week in the field, but only recorded something for 1-2 days. My batteries were still at 4.3 and 4.4 volts.