We use a slightly different setup in the plane, but I recreated the problem on my desktop using USB and the telemetry outputs. It seems that even connecting just the cube to the computer using USB recreates the difference. The problem is that while the Black Cube achieves a 100 % telemetry throughput, and 0 dropped packets in MavProxy, the same firmware (tested with several, including 4.0.9) and config on the Orange Cube gives a throughput of 96 to 99 %. When using dual links that both go to the same MavProxy, it seems that whatever is called Link 2 is down to 96 %, also using hardwired connection. When using radios in the field, this is further reduced, while the Black Cube keeps better.
I cannot see any good reason for the Orange to perform worse than Black. I would even expect that if any of them got problems with high telemetry rates (which I am not using) it would be the opposite way.
Is there a known parameter I should be aware of that needs to be different for the different versions here, since they use different processors, and probably then different clocks etc.