I have started using a stereo setup.

chain ELECTRIC GUITAR thru SPARKLE and other pedals and into a LINE6 leslie pedal, out of that in stereo to the stereo inputs of the HAZARAI and then to the amps.
I get an odd small ground-like hum this way, while i have NEVER had a cround or noise issue in mono.

DIFFERENT issue:
Last night, doing an ACOUSTIC GUITAR gig and running this pedalboard in stereo into a stereo PA head, any time I engaged the HAZARAI, I got a very solid odd smooth steady hum that did NOT seem related to ground or power line pitches. somewhere betsween 150-300 Hz (guess.. I will try and replicate it)
the tone vanishes when I footswitch-bypassed the HAZARAI.

any thought?

thanks