Official Mumble VoIP Forums

I'm having the exact same problem. Did you ever figure this out?
Help! I can't seem to set my PTT input to something like a simple keystroke such as "\" or "`". Is there a reason for this? The game I play while using Mumble (WoW) uses most of the other keystrokes so I have to use the keys that are not bound to game functions. What inputs can I use for PTT?