Used my SQ6 for the second time live tonight. During my initial scene setup, all seemed normal. I always start my sound check with all channels muted, and of course work thru each member, unmuting as I go down the line. I hadn’t even started my sound check, and as soon as I turned on the monitor amps, my wedges started feeding back. I ran to the SQ, only to find everything was still muted. After I turned the amps back off, I went back to the board to look things over. All input channels, FX channels, groups, DCA’s were muted. The only mutes that actually worked were the mix mutes themselves. Turning mix mute off showed passing audio, even tho all other channels were muted, hence my feedback issue. I was never able to resolve the issue, so I had to preform a factory reset on site. Once I did that, the SQ started working normally again. Any help in why this occurred would be greatly appreciated!