I have one pod HD500x and I have one BIG Headache!
First of all, I read and read and read and read again. I have one ENGL Blackmore signature head.
Using 4 cable Method = Hum noise.
GUITAR -> POD-> |POD FX SEND-> ENGL INPUT -> | ENGL FX SEND -> POD FX RETURN | POD 1/4" LEFT OUTPUT -> ENGL FX RETURN
Using 3 cables = no noise.
GUITAR -> ENGL INPUT -> | ENGL FX SEND -> POD FX RETURN | POD 1/4" LEFT OUTPUT -> ENGL FX RETURN
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SO, NOISE COMES FROM POD FX SEND.
To have same signal strenght (as the guitar pluged direct to amp) I have to mute channel B in Mixer and Center Channel A with more 5db. ___________________________ I use noise gates, hard gates, but nothing stop hum noise comes out from fx send.
I dont use any amp simulation, no cab, and I try with new blank pacth only with noise gate in front of chain, mixer +5db, FXloop, nothing more.