Just an FYI
Sad to report the iRig Keys I/O is not working at all now without any changes to the system - works fine with Stand-alone Sample Tank, Syntronic and EZ Drummer and also works in Presonus Studio 3 and Ableton Live - it appears its just a Sonar issue. (All of this spanning two days, multiple system/application restarts and shutdowns)
Sonar also becomes unresponsive until the Keys I/O is unplugged from the system. Time to learn a new DAW I suppose
BTW, FWIW I completely removed Sonar and made a clean install as well...