UR44 and Facebook Live

I am wondering if someone can help me with this:

Here is my set up:

I have an Imac running Catalina 10.15.6

I have a UR44, which I have had for a long time and really like it!

My goal is to get the best sound possible out of my hardware, when Im play guitar on Facebook Live.

Here is my set up:

I plug my electric guitar into Input 2 at the front of the UR44.

I run Logic as my DAW, which I use to add effects to my guitar signal (plug ins for distortion, delay etc). I alos load a backing track in Logic, which I play to. So, in essence, Logic is spitting out two pieces of audio 1) the backing track, and 2) my guitar playing over top of it.

I send one of the headphone out jacks, to Input 3 on the front of my UR44, via a 1/4 patch cable. (I am sure there is a better way). Doping it this way sometime gets me a whistling sound, or sometimes a sound that sounds like ti has effects on it. In other words, not a very good sound. Certainly nowhere near the sound quality i know the UR44 produces.

I use a software product called OBS, which basically enables me to tp use my Ipad as a camera, for streaming video to Facebook Live.

Streaming the audio component is what i need help with.

I find that the guitar signal is sometimes too high in volume for the backing track. IO also find that i can’t make the backing track loud enough.

Forgetting about what i said about my set up, how would you go about setting it up to go live on Facebook? How would you rig things up?

Thank-you