Logic 9.1.8 and duet firewire

A while back I downloaded the 9.1.8 upgrade and ran into a problem with the Apogee Duet (firewire) Maestro software software version that I had. I had repeated problems with Logic that I solved by reverting to Logic 9.1.7. Then I downloaded a previous version of Maestro intended to work only with 10.6.8. Everything was fine but I was back on 9.1.7. Recently I decided to try installing 9.1.8 again, this time with the old 10.6.8 version of Maestro. Everything appeared to be fine but I was only working with software instruments and not doing any audio recording. When I tried recording my guitar I ran into a completely different problem. I could arm the track, no problem, but when I tried to record while listening to the playback of the other tracks the record light in the inspector began blinking and the guitar track was muted. I could hear the other tracks but not the guitar track. When I stopped the playback, then I could hear the guitar track. I recently moved my logic projects to a different hard drive but this was a new project and the recording path certainly seem to be pointed at the right hard drive. I have no idea what is going on here. Any help would be apprecaited. I have an early 2009 2.8 intel iMac, 4 gigs of ram, running OS 10.6.8. I use it in 32 bit mode. Thanks

Greg