Hey, Phil, will take a bit of work, but whenever something like this happens, it's all about the "process of elimination".
-different bluray disc. If that fails still, I think two in a row is pretty solid evidence it's not your current BD.
-think of a friend, anyone, who has an HDMI receiver with decoders. Ask if they would humor you for only 10 minutes or so. Bring over player, hdmi cable, plug it in, fire it up. If it works, great, if not, it may be your player. Easiest would be if that friend has a BDP currently bitstreaming as well for the moment.
-more difficult would be bringing a different receiver into your home, for obvious reasons.
basically, we need to figure out if it's the player or receiver at fault. Sure, it might be the disc, but I consider that a very outside chance.