Here’s a recommendation: when setting up the aggregate device, select the H9000 first so its 16 input channels line up with its 16 output channels. Then, select the headphones second. This way inside of your DAW, if you’re setting up sends or inserts, the I/O is not mismatched.
Can you describe how you’ve set up your session to send signal to the H9000 and back? When I use it in a Pro Tools session, for example, I have I/O USB 1-2 mapped to an Insert. I put that insert on an Aux track. When I send signal to that Aux track via a send, the audio gets routed into the aux track, out USB1-2 into the H9000 and back into the track from Input USB1-2 and that aux track is sent to the Master Audio channel, which should be directed to your monitors/headphones. I run my H9000 in Kill dry so that I’m only hearing the wet effects on the aux track and I mix to taste. How are you doing it?
