VPI Speed Problem

I have a VPI Super Scoutmaster with SDS. Fabulous sound, had it for about a year. I moved to a new place about 5 months ago and have had it set up and working well for about 3 months in the new location.

Recently, I thought the first song on some album sides sounded slow, but as the album played a minute or two, all sounded right again. Now, everything sounds slow all the time, both 33's and 45's. I tried bypassing the SDS, though there is no speed setting on the motor assembly, so I don't know if that should sound right, but it sounds very slow and muddy as well.

Any thoughts on what might be wrong or how to troubleshoot? Any insight would be appreciated.