We have a couple of AmLogic TV Boxes with Kodi 16 running on Android 5.1
Day before yesterday one of the boxes lost all audio within Kodi. Nothing had been changed or added for a month and the box was being used without any issues every night.
By all audio I mean to say that my wife was listening to a TV show, and all of a sudden the audio simply stopped working. No lightning outside, no power failure, the audio simply stopped working. Since computers generally don’t have highly recommended quality software which inexplicably stops functioning, my first thought was that we had a hardware failure either with a cable or with the sound device on the AmLogic board. I knew that the speakers weren’t an issue because they’re too big and with safety fuses to simply blow out.
First I shut off the box, pulled the power cable, and let it sit for 5 minutes. Back on to no joy. Bummer! Replaced HDMI cable then, but still no difference. Replaced the optical cable, once again no difference. Took out the optical cable and replaced it with an audio cable plus adapter for our sub-woofer speaker connection, nope, again no difference. Beginning to get frustrated and annoyed … so now we connect directly to the TV for sound, instead of the TV Box. Video was still coming from the Box though, and yup, again still no friggen sound. Geeez, what the F … okay, decided to rethink this whole thing and start fresh the next day.
Next day … decided to do what I was trying to avoid all along, by doing a total factory reset of the TV box.
(didn’t want to lose previously installed apps and Kodi settings)
Well color me silly … SOUND WORKS PERFECTLY FINE !!!
So if anyone out there experiences a total loss of sound, you might want to consider the factory reset first. Now I just have to figure out how to save all of my settings … 
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