Interesting. Are you hearing actualy pops and clicks that are sounds not apart of the songs or things more along the lines of pauses, stutters, skips. How often are these happening and any specific time in a songs?
It's a bit hard to explain but I'll try. The songs do not skip or pause. They generally appear to play through at the normal rate. What I hear is more like little glitches, like someone is brushing a piece of paper across the singer's microphone or something. The noises are softer than the music, which is helpful, but they are definitely noticeable.
When the problem exists, it starts as soon as I start playing the music, usually making the noises every 10 seconds or so (yet random).
I should note that all of my music is ripped to my hard drive. None of this is with CDs.
BTW, is it possible for digital music to be slowed down or speeded up depending on what's happening with the PC? I swear there's been a time or two that songs sounded slower than they should have been- a problem that was, again, cured by a reboot.