Very strange. Usually when you have something like this happening with a soundtrack, more often than not it is a change in the source or source set-up but the fact that you have tried alternate sources with the same material, indicates that if everything is defaulting to PCM, on the surface, it seems to indicate that there is an issue with the Dolby/DTS decoding chips.
For starters, I might suggest you send an E-Mail to Yamaha H.O. under "support" and explain your problem and the troubleshooting you have done so far. I have owned several pieces of Yamaha equipment for years and except for one older unit where one of the DACs failed, I have never had an issue with any of them.
Based on my experience, they will usually get back to you in a day or two to advise what you can do and if repair is required, an authorized service depot in your area.
Incidentally, if none of that works and be that as it may, I have a Yamaha RX-A2000(Aventage series) in another room that I might be willing to part with.
I would not point the finger necessarily at the Yamaha.
I have a Sony blu-ray player that suddenly started sending everything as PCM too. I took the player and moved it to a different receiver and it did the exact same thing.
I happen to have a Panasonic and it works perfectly fine with both receivers. Needless to say the Sony was donated to a family in need as they could use it as is, and I needed a unit that worked.
Thanks for the replies guys!
I was literally ready to pull this unit out of my rack and order a new Anthem MRX 720, but luckily (for my wallet anyways) I tried one last bit of troubleshooting last night which has fixed the issue.
I unplugged the receiver's power cord from my Furman power conditioner, and then I simply pulled each HDMI cable from the receiver one-by-on and then plugged them right back into the same slot they came out of.
I also pulled the HDMI cable from my TV, and then plugged it back in.
I plugged the receiver back into the power conditioner and boom, everything is now working again!
I have no idea what may have caused this, and hopefully it doesn't come back again.
I figure something was hung or cached on the receiver, and even the factory reset didn't release it, as the receiver always had AC power.
