@Gurungamrit
Some pointers which might help:
– Set the USB output mode to Stereo
– Stereo link a pair of outputs and set this to Post-Fader
– Set the Stereo LR out (the last stereo option in channel assignments in the CONFIG / USB screen) to this output
– In the fader screen, select this output using the sends to button
– Set all send levels to this output to 0dB EXCEPT the guest channel, presumably the return from the phone? keep that at -inf (off)
What is now being sent out to your phone is everything except the return from your phone, and any changes you make to the main LR output will be reflected in the post-fader output.
You can listen to the main LR output by not having any headphone button turned on, so you can still hear everything including the guest/phone.
This does rely on the fact that your guest is sending their own audio to the stream for viewers to hear, as of course it would be impossible to both send their audio to the stream for everyone to hear, but also not have them hear it if they’re listening to that same stream.
Thanks,
Keith.