Ray, Firstly, what system and version of GW are you using?
I have WindowsXP home on my downstairs laptop, Jaws V10 and GW V5.70 with associated Jim Grimsbey scripts. My speech is routed through an external synth but I do not get jaws babbble. My upstairs desktop machine is a Windows7, JawsV14 and GW V5.70 system. My speech and other system sounds are routed through an audiotech internal soundcard, all others through can't remember what card. again, no Jaws babble. I suspect it's something to do with verbosity settings and check the help for the scripts, you can toggle such things as labels and progress messages. I have never needed to use any kind of passthrough key, all movement functions so far used work straight away, just ensure in the view menu ScrolLock is checked keystroke for this is control with l. I always have my recording control window hidden. I sincerely hope you have enabled the scrub feature, found on the play control following the wind settings. By default it is 0.000 mine is set to 0.150 this gives me adequate feedback when moving arrow or marker or cursor keys and certainly speeds editting by a good 90%.
