Hi! My team and I are working on a research project on marine bioacoustics. We are using Hydromoths both in an aquarium and deploying them at sea.
The one we deployed at sea was left for one month and a half. When we retrieved it we saw that the green and red lights were flashing, indicating some kind of recording failure. We checked it and indeed only 10 days had been recorded properly (15min every hour); the 11th day did not record properly producing files of only a couple of minutes; and from there on, there were empty files for the following days.
The ones we used in the aquarium (2 devices) were left to record for 24 hours nonstop, generating 24 files of 1 hour each, and we had no problems for 2 complete days. However, the third day that we set it to record, they both showed an error flashing the red and green lights as well. We saw that no files had been recorded properly on any of the devices, either only recording some minutes or just recording empty files.
The SD cards are all Samsung 256G, they are not full and still work when connected to the computer.
For the one we deployed at sea we tried changing the batteries only (still showed an error) and the SD card only (still showed and error) and then both things and it finally worked.
Based on both cases, we concluded that either the device is not reading well the SD cards or the SD cards produce a recording error after some time.
Why would the device when using Samsung SD Cards produce this error? Any ideas how we could solve this problem?