If you're using procaster it's very easy to make the viewers hear you AND your vent. partners:
- Open Procaster preferences
- Switch to "Audio" tab
- Press on the button left of "Open Audio Mixer"
- there you can see several sources!
- put source 0 as your mic!
- put source 1 as your "Speaker's Audio"
--> the viewers now will hear you AND your vent. partners.