Numark PT-01 Portable Turntable Problem.

Hello,

I have a problem with my Numark PT-01, it seems that plays at an inconsistent speed. I first noticed it when I bought it after an old B&O record deck of mine 'gave up the ghost', and liked what I'd read about the PT-01. When I play records with fairly long tones on it, it seems the speed of the record speeds up and slows down(and so therefore the sound pitch) and casues a kind of slightly of warbley, quick then slow type of sound. The dealers I bought it from were very helpful and let me try another, but it is exactly the same. I have contacted Numark, who have got back to me and confirmed that they have never had any other complaints about the PT-01, and that it is generally well received - which is does seem to be.

I'm not really a hi-fi expert, I'm sure that I don't have that good an ear for music - I only have a very old Rogers valve amp (that seems to have electric surge fights with my fridge and other household appliances, (but somehow it seems to sound nice), and a big old battered pair of seventies Warfedale speakers, but I'm sure that this Numark is not keeping even speed.

Any advice? (other than get rid of it!)