clutch pressure plate chatter on 1992 BMW 325i

I have a 92 bmw 325is and just had clutch replaced 10 months ago. When I let out on the clutch with vehicle in any gear i get a chatter like the pressure plate is chattering. The shop says they think it could be the flywheel but $600 to tear down and find out Is the flywheel machinable, if so shouldnt this have been done or brought to my attention by the shop at time of clutch replacement?

Asked by for the 1992 BMW 325i
not if wasnt a problem. if it has been fine for 10 months, then chances are that it was ok at the time of the replacement and has warped from heat build up over the past usage.

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