Sorry... a room isn't going to make the music grainy. If your signal starts out like crap..no room or speaker will change it.
First, did I say it fixed grain? Did he even say he has a grain issue? You are reading the word "grain" somewhere into the thread. I didn't see it. I certainly didn't say it.
Second, you're right about a room not being able to fix the specific "grain" problem, but a speaker and room can create some reflection problems, phase, frequency response, time, and distortion issues that lots of people would consider fatiguing.
These problems are far more real and of higher magnitude than any electronic induced problems, unless you use pure shit for a front end.
Look, he hasn't even heard his system in his new place with his new speakers. Now, I'm fine with upgrading for the sake of upgrading, but I think the smart move would be to wait....
If I remember correctly, his speakers have a titanium dome tweeter!
Now, which do you think is more probable, his electronics that likely measure flat are producing the fatigue, or his speakers with a titanium dome tweeter in a room that is likely untreated?