I was just having this problem too- did all the normal checks routing etc... after 2 weeks I looked at my channel settings in the Master group (right side of information settings) and I had (ATMOS) clicked on- which I would have had to even put there- must have been an accident or a bug because I have never used it and didn't know what it does- now I do...IT STOPS SOUND FROM COMING OUT OF LOGIC when it otherwise would/should ? so I turned it off! tadaaaa I have sound again. SO, maybe carefully check what you have going on there and maybe for some reason or other- it'll fix
cheers