I got 2GB Sansa Mp3 player, as a complementary accessaries with Nikon CoolPix L20.
My Mp3 Player freezes, when I am charging it and accedentally unplug it, witout ejecting it. Some time it hungs while plying Song.
After couple of try I found few solutions that can reboot Sansa MP3 Player, and it works with my Sansa MP3 player.
1. Turn ON the Hold switch. (move hold button to Hold Position)
2. Press and hold Menu and Rec buttons at the same time until the Sansa MP3 player reboots.
Alternate Solution is :
Hold Menu (Power) button for atleast 20 seconds. Sometimes this trick works.
To perform hardware reset on the Sansa Express, press and hold the "Select" button while pressing the Volume UP (+) buttons simultaneously once.