Sound coming from only one channel??

I have been successfully running Pro Tools Express 10.3.4 on my Windows 7 machine for a month with the Fast Track Duo. When I opened it up yesterday, I was only getting sound out of the left channel. When I go into the Windows sound manager and have it test the FT Duo, it plays sounds out of both speakers. I have tried different cables, unplugging and plugging in again, restarting the computer, etc, but I'm still only getting sound from one channel. All other sounds work on both channels, just not ProTools. Can anyone help me out?



Thank you!