Dude, I have an MD Player too! lol
Anyways, the clicking, if you know it'* not from the music you have, and if you can reproduce it on the radio [ie w/o a tape], then it'* probably something up with the HU. The wiring and speakers cannot be consistant like that. My front passenger'* speaker [the 3.5"] will produce nothing but static upon turning down the volume, or when turning the HU off, then back on within and hour period. This just goes to show you, my system likes to be louder
. It clears up after a few minutes, no matter what, though.