This is an easy fix.
Download the service manual from vinyl engine. This table shares the drive system with the PS-X5/6/7.
Fixing this issue is described in the service manual. You have to open the bottom of the table. In there, you have to loosen a wire, which disengages the x-tal lock system. Subsequently adjusting the speed pot until the speed is as close as possible and finally re-fixing the wire.
Good luck!