the only thing different about the unit is the phono cable.i have a multimeter,how would i go about checking the integrity of the cable? i just tried unhooking the phono cable from the pre but get noticeable distortion from my left speaker only when i play a cd.cheers.
I'm not sure I'm following your point about cd distortion, but it sounds like it could be a problem in your selector switch as suggested by Dweller. If moving it back and forth has an effect, you may want to go further and buy some selector switch cleaning solution and give it a good spray. In my limited experience, selector switches are as problematic as are IC's with the kind of symtoms you describe.
As for checking continuity with your multi-meter: Set your multi-meter in "continuity mode" or "buzzer" (depend on your meter but they'll call it comething like that. Then test each lead for continuity and shorts. For continuity, you touch the meter probes to each end of the cable. If it's good, the meter will buzz, (if not, no buzz). For shorts, touch one probe to one + end, one probe to the ground sleeve. If there's a short the meter will buzz, (if not, no buzz).
Of course a quicker and easier way to eliminate the interconnect as the problem is to try another interconnect.