I have read through a ton of post regarding how to check and diagnose a fireplace where the pilot or burner wont lite or stay lit, but I have not found anything regarding "wont turn off".

The fireplace seems to function fine, when you use the adjustment knob on the gas valve, off turns it off, pilot lets you lite the pilot, and On turns on the burner. What doesn't seem to work is the On/Off toggle switch located near the gas valve, Off doesn't turn the fireplace off and the wall switch does not turn off the main burner.

Thoughts? Stuck open valve?