Accelerometer not working with phone calls?

[Marty]

I can no longer get my Sprint TP to silence an incoming phone call or mute a phone call by placing it face down. I know that this function worked fine about a week ago but no matter what I do, can't get it to work at all (haven't installed any new programs since then either). The accelerometer does seem to be working fine though within Opera Mobile as it has no issues switching between portrait and landscape modes. I have tried recalibrating with the G-sensor app but still no luck. Anyone else experiencing this and/or have a solution other than a hard reset?