VirtualDJ Crossfader & Audio Fix

My first priority is to stop hearing both decks at once through my Bluetooth headphones when the crossfader is fully to one side in VirtualDJ. I am running only a laptop (no external controller or sound-card) and the headphones are paired via Bluetooth.

I need you to:
• Walk me through the correct audio settings inside VirtualDJ so the crossfader behaves properly and I can pre-cue one deck without it bleeding into the master signal.
• Explain any Windows / macOS sound-panel tweaks that might be interfering with the software routing.
• Show me how to test the fix live so I know the mix is clean in both the headphones and the master output.

Once the crossfader and cueing are behaving, I’d also like a quick overview of how to route the master audio out to a streaming platform (OBS or similar) so I’m ready for live broadcasts, plus some starter tips on beat matching.

We can screen-share; I’m on the latest version of VirtualDJ. Please outline how long you expect the remote session to take and what follow-up materials (screenshots, setting files, short cheat-sheet) you’ll provide so I can reproduce the setup on my own.