Tony , let me put it this way . When I listen to a CD in my car on my Alpine cd player it sound mind blowing . Very nice high and mid range . When I listen to the same track on the Empeg there is a loss of high-frequency and the signal seems dirty , just like you say , there is noise with / in the music. I never did notice the stereo shifting or other stereo problems. I don't listen to music on my computer , I would never keep up with my car system . I do listen to mp3 with my Empeg hooked up to my Musical Fidelity amp and Dynaudio speakers , same problem as in my car . I will work on it , learn a thing or two and see if I can fix my problem. Thanks for the support.