When you plug in the CM15A, are you unplugging your other transceivers at the same time?
Is the CM15A connected to a PC running AHP when you plug it in?
Is there any programming (macros, timers, etc) stored in the CM15A, or in AHP on the PC it is connected to?
What does the Activity Monitor show when you press the Blue buttons?
Do the other buttons (the on/off ones) still work with the CM15A plugged in?
What House Codes are slected in the "Trasceived House Codes" section of the AHP Hardware Configuration?