viavoice won't work

I have used IBM viavoice to dictate emails etc on my mac for years.Since one of the recent OS Xupdates it no longer works. I assume it is caused by an update because i have the same problem on my powerbook. When I open the program, it says the microphone (I use a USB Mic) is in use by another application. I don't see any other app using it. Activity monitor just shows kernal stuff. Any Ideas?
I saw this problem on an old forum--any new solutions?? IBM support site very confusing at least for me. I am trying to use IBM viavoice 3.0
thanks
jl