Thanks for your reply. I think my setup is fairly conventional: My guitar goes into a Strymon Iridium, then the left and right output from the Iridium is connected to inputs 1 and 2 on the H90. Outputs 1 and 2 from the H90 go to my Audient interface’s D.I. inputs.
As I’ve spent more time with the unit I’ve noticed that some patches are quieter and some are louder, so what I’m noticing is probably how the sound designer intended it to be. A master volume won’t fix that, I think I just have to tweak the patches I like manually.