PX4 not detecting camera hearbeat

Hi
I have camera connected to the UART telem port of PX4 with PX firmware. I have the board connected to PC via usb cable and QGC running on the PC.

The QGC does not detect any camera, since it does not hear any heartbeat from MAV_COMP_ID of camera.

However, when I connect a board woith Ardupilot FW instead of PX, the camera HTB is detected and I can control the camera via QGC.

I am using PX4 Pro Stable Release v 1.11.3 (upgraded via QGC as latest)

Is there any reason why I can’t detect the camera with PX?

Parameters of MAVLInk as set in qgc:
MAV_0_CONFIG TELEM1
MAV_0_FORWARD 1
MAV_0_MODE Normal
MAV_0_RADIO_CTL 1
MAV_0_RATE 1200B/s