Volume + "shuts off" Sansa Express

Our Sansa Express 1G “shuts off” when pressing the volume + button.  We were using firmware 01.01.05, but about an hour ago I updated to firmware 01.01.12A – and the problem persists.  Since the device volume is “stuck” at the lowest volume level, the device is unusable as is.  When I “turn on” the device, I receive the “building database” message, followed by the Music menu item.  I’m using Windows Vista Home Premium. 

How can I fix the device so the volume + button works properly?  Thank you.