I have this same player and have not had this problem but i know how it happens, there is a problem with the boot loader. You have 1 option, deal with sansa support and have them send you the fix file via e-mail, putting it in recovery mode (turn on, switch to hold and hold REC. button) transfering the file they sent you and following the instructions on the screen.
Yo prevent this i recomend loading rockbox, it vertually partitions your sansa to boot into the rockbox os wich plays everything that the sansa played and all open source media (audio). instructuions in detail are at www.rockbox.org
Im also having this problem...i cant seem to find a solution although holding power down does switch it off when this happens
You need to hold power down for 15seconds then try turning it on again. mine only works after holding power down for 3sec then if it fails i need to reset a g a i n for 15sec. most of the time i need to try 3 or 4 times before it comes on.
I took out the battery and put it back in. It then worked.
Thats it.. the only solution is to charge it FULLY then see what happens. if that doesnt work.. .THEN IM GETTING AN EXCHANGE!
You'll Have to return it. It is a glitch with the software
Hopefully you find an answer, because i am having the exact same problem, please post your answer
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