Thank you, I do understand all that and I have successfully done many livestreams and tests using Producer, but not going through OBS. This appears to be an issue with the bitrate I have set in OBS. It's probably that my system doesn't have the capacity to run all this stuff... I think, like the error indicates, the problem lies in the bitrate of my video source but I don't know how to fix that.
FB makes a number of simplified choices when streaming from a mobile device. Once you stream from a PC (including OBS) then FB gives you more control... so you have to set more details, click more things, etc (simplicity vs control).
Though I didn't notice if you indicated, I'm guessing you are NOT using FB's Scheduled Live Video, right? In which case, in OBS Start Streaming only sends the video stream to FB [with OBS properly configured, it will send stream to FB. And in LIve Producer, ypu'' get the preview window]. You have to chose within FB Live Producer, as
@qhobbes notes, to "Go Live"
Again, if you start streaming in OBS, and you get a preview video window in Facebook\Live\Producer, then basically OBS is all set [plenty of tweaks/optimizations depending on desired outcome... but you are good to start]. Note I said "preview" window. To actually tell FB to stream that content to configured destination (everyone, or whatever you've set) is done entirely within Facebook, and Facebook has documented the process. I found following FB directions to get a stream broadcast fairly easy. It was the implications of the options, and optimizing the quality of the stream that took effort (and some of the nuances of Scheduled, that I/we needed)
Also, note when you first go to Live Producer, the streaming destination page listed (middle left side of screen). For me, it defaults to a personal page, and I have to change that to group page