i recently had the problem where when i turned the on switch on nothing happened. there are plenty of websites that tell you how to disassemble your player, which is what i did and it turned out i had a loose connection.
to be honest tho the vision m was a bit broken before it totally died, and i haven't got it fully functional as of yet, but it is at a fixable stage now.
hope this was helpful
helen
September 2008