Mailist to discuss all issues regarding the Digitech GSP-2101 Guitar FX Processor

Thanks for all the input so far.

The cable I use (plugged to the ctrl one jack of the 2101) is a new MIDI cable 
with all 5 pins wired, so the control one gets its voltage and apart from the 
hum works as it should (display, program switches, expression pedal). It's 
thinner but shorter than the original cable I had with my first 2101. I 
didn't open the plugs yet, should the plug housing be grounded? Should the 
cable be shielded? Does anybody know the pin assignment for the MIDI cable - 
on which pins is the voltage and how much should it be?

How can I tell a high quality MIDI cable from a bad one?

I agree that difference in grounding or wrong grounding is often the cause of 
hum but I can't see how that could happen in this case (except if the MIDI 
cable had a grounding/shielding problem - which I don't know). The devices 
are plugged into the same circuit and I had my old 2101 and control one 
working without problems at the same place.

Thanks again,
Helmut