I've experienced this also.
Previously I had about 300 songs on a 4GB class 6 card. No problems at all playing music. I recently moved to a 1250 songs on a 8GB class 2 card and that's when the freezing began.
I've tried different roms and the latest one worked for a couple weeks actually but now, once again, nothing plays.
What speed of card is that card and how many songs do you have?
I really have just given up on the touch flo music tab and switched to Nitrogen.
http://freewareppc.com/multimedia/nitrogen.shtml
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