Please follow one of the steps depending on your set up -
Muting MR for yourself while your stream can hear it:
1) Make a new overlay in the editor, only add the Media Request widget.
2) Add a new browser source in OBS, add the URL and set the dimensions correctly.
3) Tick the checkbox for to Control audio via OBS
4) Go to Edit > Advanced Audio Properties and set your MR overlay to Monitor Off
Note: This will play through Desktop Audio, if you mute your desktop audio, it will mute MR
Control audio separately from the stream:
1) For this you will need a VAC
Make sure to go over the guide to exclude audio sources for a stream or recording, and the VoiceMeeter Banana guide
2) Run your MR either in Chrome or in Ground Control
Do not click on "Show on stream"
3) Set Chrome or GC in the VAC as an audio input and output
4) Add the audio output from VAC as an audio input in OBS
This will not allow showing the video in OBS
It is currently not possible to separate audio for yourself and stream if you also want to show the video in OBS. The only way to do this would be to follow the last set of instructions above and then use Window Capture (in OBS) on GC or Chrome.