Turntable speed problems...

I had to re-set up my turntable after replacing my phono cables and phono cables and I encountered a problem which borders on the bizarre and was wondering if anyone has experienced it or something similiar to it.

About 5 minutes into playing a record, the speed of the turntable "jumps" appreciabley faster (my turntable is a SOTA star). It is extremely anoying for only that time when the speed changes. After the speed changes, my ear becomes used to the newer speed, and my teeth stop grinding.

Has anyone encountered something like this? I suppose a fly-wheel might be on order (to regulate the speed), but why am I having this problem now when I have owned the turntable for 14 years and never experienced a problem until now? I still run the SOTA into a Trip-lite (just like before)

Thanks for your help.

Sounds to me like motor failure, I would guess that soon you will turn it on get nothing. The fact that you moved it or re-connected it is just coincendental. Start looking for a motor, I had Pioneer PL540 starting to do that and that was the perfect excuse for a new turntable.
I agree to Theo. Have the same problem with my Transrotor Electronic. In this case it very likely is some elctronic part in the speed adjustment section.
Maybe it's an excuse for a new TT :-)
If it always does it in the same place there may be other possible problems. As a test, remove the belt, position the tonearm just before the speed change occours, spin the platter by hand and then lower the arm onto the record. If the platter does not spin freely, it is a bearing problem or the bottom of the platter is making contact with the plinth. Likewise, if you still hear the speed change, though spinning by hand will not yeild 33.33 RPM, you still may be able to hear it, then it is not the motor and other causes must be looked at. Leveling the table is very important and may also be a consideration. Finally, the good folk at SOTA are a wealth of knowledge and are generally willing to go out of their way to help. They would be your first resource.