Help my keyboard

I am preparing for a series of live recordings and have successfully transferred my AA3.0 license to a faster machine. Testing all the settings, I remembered that I also had made a change in the keyboard settings. The native setting of Audition is to switch from recording to playback when the space bar is hit. This is very dangerous in my situation since no other key is hit as easy unintentionally as the space bar, and in a moment, part of the take has gone ! In AA1.0 I could change the assignment, and it seems to be possible the same way in AA3.0. However any combination replacing the spacebar has no effect, and the problem persists.
I should add that I am using a Swiss German keyboard but with all the correct settings in XP. Any one giving me a hint ? Thanks in advance.