My 6006e Ford stereo doesn't accept CD's?

When a new disc is enterd into the player it overshoots the mechanism that grips the centre hole in the disc. This results in the disc not being located when the unit attempts to play the disc (a loud grating sound is heard). I have removed the unit from the dash and removed the top cover. With this done I can prevent the malfunction from happening by physically holding the disc back and locating it manually. If a disc is ejected but not removed from the unit it sits there for a while until the unit pulls it back in (correct mode of operation). In this mode the disc does not over shoot and works perfectly. Has any body got any advise before I launch the unit through the windscreen.

Thanks

Jonny