Hello Heather,
The belts should not be rubber they should be orange toothed neprene that hardly stretch, what can happen is that the nylon teeth on the belt could wear down, open the end up and have a look, if the belts look okay make sure they are very tight, you can adjust the screws on the motor to tighten.
drivewithken
October 2010
I can answer this question...
How do I change the belts on my Frister Rossmann 502?
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