I have posted this question on both the Ardu and PX4 forums and have not been able to find a definitive answer. I have a hexcopter with a CubeBlue and Herelink system running the latest version of Ardu firmware. I have a companion computer connected to TELEM2 using a serial-to-USB adapter. The TELEM2 port is configured in QGC correctly as MAVLINK2 with 56 baud and standard port configuration. If I boot up the companion computer and Cube, the cube will not send any MAVLINK data over TELEM2. To make this work, I can first connect QGC to the TELEM2 and once a connection is established, I can disconnect QGC and plug in the companion computer. At that point, the cube will send MAVLINK data over the TELEM2 port.
This behavior is not seen when running on a Pixhawk6C running PX4 firmware. I was wondering if anybody is familiar with this issue and if the Cube is waiting for something to be received over the TELEM2 port before it starts to send telemetry?