Since you have not had the problem with other sources, I can't help but think it is in the amp or preamp.
All the other sources run through the same amp and preamp. So are you saying that it could be failing at the amp or preamp just based on the demand of the bluray and that the other sources are not demanding enough to push it to fail. When it does happen the amp and the preamp do not seem to go into protect mode. I thought I would see something at least on the amp that that channel was in protect mode. I will try some off the other ideas posted here and see if I can get some more results. I don't think it is the m80s either, since they don't seem to exhibit any othere problems.
