I've done a lot of work and watched several videos and was able to configure the X32 to bus 5 & 6 to USB out. But when I go to "Sends on Fader" I still don't have control to mix the out differently than the main outs. In fact, when I mute the channels so that no sound is coming out of the mains or the monitors I still hear sound from the USB out; even if I mute mix bus 5 & 6.
If I unmute the main channels then they'll increase in volume in the USB out but if I mute the mix bus it has no impact on the sound.
I'm positive the routing is done correctly to send the mix bus 5 & 6 to USB out.