Quote Originally Posted by hamish View Post
probably a stupid question... but is your mat flat.. i was using a roksan mat to start with on mine and it was hard to get it to sit flat for some reason - it did the exact thing you are discribing...

other wise you sound like a good candidate for dave/mikes new's new platter when its available
Given the vast number of platters produced and the usual level of precision they are made to (just look at the strobe 'knobbles'), as manky mat is FAR more likely AND much easier to fix.