Hi, is it normal for the HD500x to hum like crazy when the guitar is unplugged but with the lead still in the device? (tested with three different leads, so no bad lead) When I unplug the lead on the POD side, the hum disappears.
Tested with only a pair of headphones connected to it and no output leads going to external amps or mixers or usb.
Could it perhaps be the lead acting as an antenna picking up interference? The tone or buzz however don't change when moving the lead, but does drop in volume when touching the ground part of the lead, but still audible.