You don’t need anything but a screwdriver to try neutron_bob’s suggestion:
“If the Sansa will not boot, it’s entirely possible that a mechanical connection to the flash memory daughterboard can cause serious headaches. To check this, remove the rear cover, and inspect the big black rectangle above the battery module. You’ll see a grey foam block there, which keeps the daughterboard pressed inward. Go ahead and give it a gentle press. If the board clicks back down into its socket, you may have just solved your problem.”
