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Sep 5, 2018

Empty Files


I had purchased 5 audiomoth devices that were places inside an airport on the fences as a part of a fauna study project. I have found that, during the tests done before setting up the devices at the study site with the following configuration: Sampling rate: 48k, Medium gain, duty cycle: 5 s off/ 60 s off, the recordings were clear as expected with filterable low frequency noise. The SD cards used are SanDisk Extreme Plus. However, at the study site, whe setup with the same configuration, there were no audio samples recorded and the only day it recorded, each file had 0 Kb worth of data in it along with 4 records with 1 min worth of data in each as shown below:



For the rest of the days, it recorded no data at the allotted times. Upon further tests outside the airport, the recordings gave the same results as the ones during the first tests.


Is it possible that there can be internal interference in the audiomoth? If not, is anyone having a similar problem?

Sep 10, 2018

Hi Karthik,

Just want to confirm, are all 5 devices having the same issue and do they always function normally when used away from the test site? We've not experienced or heard about any similar issues before now.



Open Acoustic Devices team

Sep 10, 2018

Hi Peter,


Yes, we have tested it out with all the devices and they seem to be having the same issue. Since the study area is in the island of Samos, Greece where the average temperature during the season is 32 degrees. Do you think it maybe related to environmental factors such as heat and humidity?




Sep 14, 2018

Possibly. Could you try deploying the devices on the ground outside in your garden for an hour or so to see if they react to the heat at all? Another possibility is the movement of the fence shaking the batteries loose. I'm not sure how windy your deployment location is but that could be a possibility.


If it's not possible to work out which factor caused the issue, then I may message you directly about getting your devices replaced and you sending us yours to analyse for hardware faults.



Sep 24, 2018

Hi Karthik, Could you confirm when you purchased the devices too? (i.e from a GroupGets purchase and the round in general?). Also, did you use a protective enclosure for the AudioMoths? Kind regards, Alasdair

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