I just tried opening a brand new software instrument track on an empty GBproject, chose Fretless bass, played a note and it dropped a semitone, then changed the input to piano and got piano AND bass. Then changed to a drum kit and got drum kit and bass, but only at the lower end of the keyboard.
I've tried a factory reset as in the iRig Keys manual and it doesn't make any difference. I'm using the correct lead and going clean into the USB port.
I can only conclude that the iRig Keys has somehow gone faulty, though I've hardly used it since I got it 18 months ago.

Help please?