Matek F765-Wing F.Port issue

Hi,
I am in the middle of a new build and was trying to give F>Port a go. So, I have r-xsr flashed with fport accst firmware, updated my Taranis with latest OpenTX, flashed internal module, hooked it all up according to instructions:
BRD_ALT_CONFIG=1
SERIAL7_PROTOCOL=23
SERIAL7_OPTIONS=15
RC_OPTIONS=8 (did not work at all without it)
RSSI_TYPE=3

The thing is, I can’t get telemetry consistent. I can discover GPS sensor for a sec, as well as YAAPU script responds for a sec, then nothing. If I hold bind button on RX, it switches to whatever other mode and I lose control (no movement reported on TX calibration page) but telemetry goes for a second again and stops. I hold bind button again, blue light comes on on rx, I regain control, telemetry turns on again but again only for a second or so.
Using Arduplane 4.1 dev (latest)

So, I have reverted back to SBUS and smart port telemetry, and it works fine.

Is FPort broken or am I missing something here?

It sounds like a setting issue. How do you have the rx hooked up to the fc?

Ground and 5v to corresponding pins, smart port on rx to T6 on FC.

I have f756 wing with 4.1 on it connected to r9 slim+ running access and the only different setting I have is the rc_option and that is set to 0. Are you using access or accst?

I always use accst if I can.