|"my computer is very slow lately and pop-ups are terrible"|
Well, those symptoms are indicative of malware, but the music? Not so much - - there are more mundane explanations. Speaker systems can, in some cases, act as receivers, and radio waves of all sorts saturate the modern world
You might consider an online scan, such as Panda - - although I'm not too sure how you can stop picking up stray signals. You might try moving the computer to a different part of the house, or look into noise filters
I'm not one of those who think Bill Gates is the devil. I simply suspect that if Microsoft ever met up with the devil, it wouldn't need an interpreter.