Weird Behavior Returning Aux The Local Inputs

SQ SQ Troubleshooting
1

SQ6. Outboard Bricasti reverb. Assign local input to stereo Aux 5 prefader. Assign local input to Main L/R. I/O assign Aux 5 to two local outputs. Return those outputs to local inputs 23 and 24 with XLR cable. Assign inputs 23 and 24 to Main L/R. Tone in input. Push up the input fader, tone to Main L/R. Kill the fader. Push up fader 23. tone to Main L. All good. Push up the input fader and the Main L/R level drops as I push up the input. No polarities, no EQs, no compressors, but if I put an XLR phase reveres in line with the Aux 5 local outputs and local inputs 23 and 24, the problem seems to go away. Also does not seem to be frequency related so I don’t know why the phase reverse barrel makes a difference.

First obvious question. What might cause this behavior?

Second question, is the a better way to put an outboard reverb on Main L/R than using an Aux send?

Thanks for any help. This is super time sensitive; this needs to be fixed today!

D.

2

Do you want to apply the Bricasti to the entire LR output mix?

If so what about using a group, set up a stereo group, assign all the needed inputs to
that group, now UN ASSIGN that group from the main LR mix, assign two outputs for that group out, those will go to the input on the reverb, take the outputs of the reverb to
two input channels, assign those channels to the main LR out and not to the group that is
feeding the reverb.

If you just wanted to use the reverb as a standard external reverb to apply to certain
channels use an aux out to send to the reverb and a couple channels or a stereo channel
to return the reverb to the mix, do not turn up the aux level on the the channel that sends to the reverb on the channel that is the reverb return.
That set up is the same it was done using an analog mixer with outboard FX units.