Thanks for the inputs! I didnt have time to try out all the suggestions, but assigning a gain block at 0dB works. But: when I assign a gain block to FS4 which I used for channel switch, it works. Then, I tried to assign another gain block to FS5 which I used for FX loop switch. It didnt work. First problem was that this gain block created for FS5 was on the right from FX loop icon (I was in 4CM mode). There was some terrible noise issue during latching on/off. So I moved this gain block to "preamp" mode. The noise was away, but I wasnt able to set it in a way I wanted. Will keep trying. I need to move my amp from rehersal room to my house so I can have more time to investigate.