[skiguy411]

I have a Zen Xtra and when I play it with the CMOY amp that I built, I can hear the hard drive spin up and little blips when I move the wheel. However, when I play the xtra without the amp and after adjusting the volume level, I cant hear the imperfections. Does this mean there is a problem with my amp?

 

[Wodgy]

No -- quite the opposite. Your CMOY is probably a better amp than the internal headphone amp of the Zen Xtra and you're hearing noise and interference that you didn't hear before, but has always been there.