I have been getting this issue since day 1 and it has gotten to be rather annoying. i do have a temporary fix every time it happens but its quite annoying.
The issue seems to be handshake related. Anyways this is what happens:
Receiver has 3 things hooked up to its input. Its output goes out to the xbox one.
The xbox one's output goes out to my TV directly.
This means the receiver is used for the audio of everything except the xbox one. The TV is used for the xbox one's audio.
How to replicate the problem:
I say "Xbox On" which turns on my xbox one, receiver and television.
Every once in a while the TV's audio does not output the Xbox one's audio (as i get no audio from the xbox one menus or apps/games i use). I would say a third of the time. It only ever starts happening after turning everything on.
I fix this problem by going to System->Display & Sound and i click "1080p" and change it to "720p". On the screen that comes up i choose "No" to keep 1080p...once i do that the audio comes back on.
Any help would be appreciated but my guess is perhaps the xbox one turns on the TV too soon (before the xbox's audio drivers are perhaps loaded?).