Do you have one amp or two? How and why do you switch outputs/amps? Is the H9 between the ES-8 and amp(s)? Please provide more info about your routing.
Sorry let me be more clear. I have two amps. I’m using a BOSS ES-8 loop switcher that has two outputs. Both outputs used to go directly to the amps. Now they go to the H9, and then to the amps. I think what I’m looking for is to “preserve the stereo image” even when that image is only one side coming through.