I've had this issue with the table as long as I've owned it.
Did you buy the TT new or used?
If you bought the TT used the motor pulley grove as well as the platter, where the belt rides, may have belt residue buildup. Residue build up will cause wow and flutter.
I had the same problem with my AR TT. Cleaned the motor pulley, sub platter where the belt rides, and washed the belt with dish soap. I also stopped using talc powder on the belt.
Note.... Be careful when you clean the motor pulley not to get any cleaning solvents on the motor shaft that could migrate on/into the shaft bearing. You only want to clean the grove.....
I used several slightly dampened cotton swabs. I couldn't believe all the black gunk that came off on the swab.