Luxman PD-441 Needs Service

I have used and enjoyed problem-free my PD-441 for mono recordings for about 2 years. Suddenly, both the 33 and 45 speeds will not lock in and recordings sound predictably horrible. I have already run up about $250 in local service fees and since they have no definitive solution in sight, I have pulled the plug on their efforts. So, does anyone know where I could have this problem corrected?
I've got a working PD-444, so far so good! Good luck. If the connection to cobra doesn't help, you might try Bill Thalman at Music Technology Inc. He is reportedly good at repairing almost any vintage TT.
Thanks, Dgarretson! I have really enjoyed my 441 and hope it can be saved.
You might PM 213cobra about it. I'm told he knows the PD-441/444 inside out.
Yes, all of the caps were replaced along with several other parts. The problem appeared to be corrected; the table ran at 33 and at 45 for hours-long periods without a hitch. Then the next day when the table was turned on and tested, the speed lock problem had returned for both speeds. Very frustrating.
Have all the original electrolytic capacitors been replaced? This should be done as a matter of course to ensure stability, and may even solve the problem.