Tue Apr 09, 2019 10:59 am
A hung note is not a Hauptwerk problem and is not something that I would tolerate. There's a possibility that the computer is having trouble keeping up, especially if the MIDI signal is running through an audio interface. The most likely problem is with the MIDI encoder, MIDI daisy chaining, or a defective MIDI to USB interface. If there are multiple MIDI streams from individual manuals or the pedals they should be combined in a quality MIDI merger which has a USB connection to the computer. Kind of depends on your MIDI configuration.
If the MIDI is going through an audio interface then check if the HW CPU indicator is going into the red zone. That would indicate that the CPU is not keeping up with the interface which could affect the MIDI data as well as the audio. Increasing the buffer size would be good for both MIDI and audio in this case.
Don't forget to consider dirty, noisy expression pedal potentiometers. Do the hung notes disappear with the expression pedals all the way open or closed? That would suggest the pots need changing out.