VPI 16.5 problem

I just recently purchased a VPI HW-16.5 record cleaner and it worked perfect for the first week or so, but now when I flip the vacuum switch, the vacuum piece moves down onto the record and it goes ok for a second, but then the vacuum is too much and the platter stops rotating and it's just vacuuming the same spot. Anyone know what the problem is?

I'm doing this with the cleaning solution on the record so it's not that it's a dry record. And I've experimented with using more or less solution, but I get the same results.