Maybe you’ve already checked, but can you capture from the webcam in OBS without any other sources? We can at least try to isolate the issue down to a single source or a conflict between sources.
That said, you should be able to capture from multiple sources (DAI, USB webcam, YouTube in a web browser) in OBS simultaneously (that’s the point) but that also assumes you have enough CPU and USB bandwidth available your PC or Mac.
You can put the backing track in a DAW (GarageBand, Logic, Reaper, Ableton) or a program like SongMaster that can provide a metronome sync’d to the track, but that click will be captured by OBS since it will be using the DAW as a source.
If you feel like going to the next level, you have more options by uncrossing the streams.
For instance:
- record video using the webcam in OBS or on your phone
- record your bass in the DAW with the backing track playing (with click)
Then in a video editor you bring together your bass audio, the video, and the backing track, giving you control over levels, etc.
It’s not really much more work once you get your setup going, and the final product will be better.
Good guide here: