Well I had this in a waterproof bag case and was careless and did not seal it well enough and a drop of water got into the microphone. and it was only the microphone that was not working tested everything.
The repair went well but i would suggest to make sure you have the right screwdrivers because i stripped one of the screws and was not able to take out the battery and that made the install so much harder to get done. but all in all the device is now once again happy and healthy and kicking on until its replacement this fall and being put to pasture as a backup in my drawer. the teardown & install took all of ten minutes even with all the problems plus five for reassembly.
check your tools and take care not to strip any screws