Note that to test this out, you can paste these into pacmd if you want to test things out. So then this is what you need to put in ~/.config/pulse/default.pa. Instead, we'll have pulseaudio direct both to_obs and to_obsmon to your speakers, and will send the audio output of OBS just to zoom, not to any real devices.

So while in an ideal world you would have two audio output streams from OBS, send one to zoom and both to your speakers, we are going to have to approach this differently. The complication here is that the only way to get sound out of OBS is through the monitor device, and there is only one. from_obs will be a source for sound coming out of OBS.You would use this, for example, if you were were playing a video for people in your zoom chat, and want the audio both recorded and sent upstream. to_obsmon will go to OBS to be recorded and sent back upstream.This will be used for audio from your videoconference, which you don't want to send back upstream. to_obs will be a new sink that goes to OBS and is recorded in OBS, but where the sound is not sent upstream.Basically what we need to do is create 2 new sinks and one new source. Here is how I accomplish this using pulseaudio.

Virtual audio cable lite