Omnibus F3 Tx3 usability

I’m trying to use a GPS, S.Port, S.Audio, and R-XSR on my Omnibus F3. The GPS is on TX2, S.Port on Tx1, & the R-XSR on the SBUS in pin. How do I use TX3 for S.Audio? I have flashed FPORT on another R-XSR receiver that I have been switching with a non FPORT receiver, and removing the SBUS wire for testing both ways, but can’t seem to figure it out. The S.Port wire still has to go to Tx1. The SBUS wire is removed from Rx3 and is combined on the S.Port wire on Tx1. It shows that Motor-5/Tx3 are shared. Tx3 looks like the place I need to attach S.Audio wire. What do I need to change in the CLI to use Tx3 for S.Audio, since I’m not using Motor-5? I’m running INAV 1.9. Is this possible?

Lookup SoftSerial

You can resource remap a UART to soft serial and then select Smart Audio on that UART in betaflight.

But if you can do that in INAV I don’t know.