bitflipper
I may be mis-remembering, but wasn't the interface test part of the WDM init routine? IIRC, it stopped being an annoyance when I switched to ASIO. sjhscoach, you might try using the ASIO driver and see if that works better. I should add the caveat that the only time I ever installed SONAR on a laptop (it was SONAR 5), I couldn't get ASIO to work due to the crappy RealTek interface and had to resort to MME. That was circa 2005, though, and may no longer be relevant.

That should only happen if there is no audio.ini file which should be written after Sonar has checked out what drivers are loaded. If you haven't selected a driver in options Sonar will default to the first MME or like driver.  To my knowledge as I recall at that time Sonar didn't support ASIO. I could be very wrong about that point though. Its been a long time.