Steve, is that a custom built plinth, or is it one from an AR The Turntable with a custom metal or wood top deck? It is certainly a very striking turntable.
Lift off the subplatter and move the belt to a different step on the motor pulley.
I suggest going to Vinyl Engine and downloading the owner's manual:
http://www.vinylengine.com/library/acoustic-research/xa.shtml
Also, do a search of this forum. There is tons of advice on how to service an AR-XA. Pay especially close attention to postings from marcmorin. These are not difficult tables to restore.
Here's a good starting point: http://vinylnirvana.com/ar-diy-do-it-yourself/basic-service-to-an-ar-xa/
Only the inner platter which has been modified with a SS spindle and ball bearing and the outer platter which is basically an AR ETL-1 platter are original AR parts. The Hurst motor has been modified by SOTW and is super quiet.
Goggle "Sound of the wood", Eric makes some nice mods and some crazy tables.
No affiliation, just a fan.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^The mat looks like an Eon Tri Pad.
That is a nice looking XB! I'm listening to my XB now and it is a joy!

If plugged in an not turned of I can feel some sort of vibration or "hum" on the pulley. Is that normal?
Any recommendation for a stylus cleaning?
Again thank you everyone for your help!
Jose