Sonar HS4.0 & Yamaha CLP-170 Clavinova - Clavinova no longer responds

 Hi, I am running Sonar HS 4.0 on a Win XP box using a midi parallel connection to a MOTU pocket express controller to both a Yamaha CLP-170 and an Alesis QSR. I have been using this setup for several years with no problems and then all of a sudden one day the CLP will no longer respond to midi commands (the QSR still works fine). I did not change any configs in either Sonar or on the CLP when this happened. If I change the MidiInChannel to on the CLP to "main" the unit responds, but any patch/volume/pan commands are ignored - it will play only 1 instrument at a time and any patch/volume/pan change gets applied to all channels. I have also tried the USB interface to eliminate the midi controller or the cable as a problem and the CLP still has the same issue. I have reset the CLP to factory default a couple of time, but that has not worked. Yamaha support says that the midi setting MidiInChannel must be set to "song" for all 16 channels, but when I do that I get no sound from the CLP. They have been unable to help me any further and they are suggest that Sonar is the problem. I have an old copy of Cakewalk PA 8.0 on the machine which I fired up and the CLP will not respond to that either. A "local" midi test on the CLP was successful, so it will respond to it's own internal commands. I would appreciate any suggestions to help me track down this issue. (Does anyone know where I can get a midi trace program so I can view the midi data being sent from Sonar? I was a computer programmer for 25 years so reading a hex data trace should be no problem for me). Thank you! Jim