Does the problem happen if you don’t install avast?
Does the problem appear when you disable the avast! resident protection right after boot? (rightclick the blue icon and select “stop resident protection and exit”)

When you play music with avast, can you see in Task Monitor that some value of some process (memory usage, objects, …) is growing, for example?
How do you play the music, btw? (what software)
What drivers do you use to play - asio, mme…? (though I doubt this one would help us much - we don’t have this nice piece of hardware to test :().