I got another undesirable 4 CM experience with my Helix and my Koch Twinton.
A very loud hi frequent feedback noise appears while the LEAD-channel is active.
Even if there is no guitar pluged into the Helix and a Plug tip from the Helix out cable is just touching any shield of any active Helix output!?!
If I only plug the Helix in front of the Koch or only to the FX Loop evereythig is ok, with the same levels!
Is it possible a galvanic isolation could help or ist it just a level problem?
Does anybody had a similar experience?
(I'm not a native english writer, so please give me a hint if something is asdöljquvwe! :-) )