Parameter download blocked when connected via UAVcast LTE (dual link with RFD868)

Ground Control Software MAVLink
1

Hi everyone,

I’m facing a strange issue when using two simultaneous telemetry links to my flight controller (Cube Orange+ running ArduPlane).

My setup:

  • Connection 1: LTE via UAVcast (Raspberry Pi Zero 2 W + Huawei E3372H)

  • Connection 2: RFD868 radio

  • Ground stations tested: Mission Planner and QGroundControl

  • Behavior observed on: ArduPlane 4.6 (beta and stable)

Problem description

When I connect through UAVcast (LTE), everything works fine at first — telemetry is received correctly.
However, once this LTE connection is active, I can no longer connect through other methods, such as the RFD868 link.

In Mission Planner or QGC, the parameter download never completes (the progress bar stays frozen).
If I manually cancel parameter loading, telemetry continues to stream correctly on both links at the same time, but I cannot send commands, change parameters, or upload/download waypoints.

Additional notes

  • The issue does not occur when using other LTE connections (e.g., OpenWRT hotspot).

  • I don’t recall this happening with older versions of UAVcast (though I’m not 100 % sure).

  • The only way to recover is to disconnect 1 connection method and reboot the flight controller; otherwise, parameter and command access remains blocked.

Question

Has anyone experienced a similar behavior with UAVcast or dual MAVLink links?
Could this be related to how UAVcast handles serial or UDP forwarding (e.g., stream duplication, flow control, or MAVLink routing)?

Any ideas or suggestions would be greatly appreciated.

Thanks in advance,
Stefano

2

I think the problem is that both ground stations have the same mavlink id. im not sure if you can just change one but you might need to connect one in read only mode using CTRL+T

3

MP and IIRC QGC do. You should configure multiple connections on one GCS and then it should work. Different GCS should have different sysIDs.

4

I’m in contact with UAVmatrix, they are super helpful as usual.

I use to use this setup (double or triple redundant connection) from the very beginning.
Also with others LTE setup (openwrt in example) this is not an issue.

5

Anyway, to assign a different ID to each instance of mission planner, is working.

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