Unfortunately I haven’t confirmed that, because afaik one can no longer flash unsigned firmware on AirOS devices with signed firmware (since 6.0.6 or so) without opening the case and attaching a serial cable / using tftp, but these devices aren’t mine. I just found this thread so maybe I could try to play with first downgrading to 6.0.6, then to 6.0.6 beta, then to unsigned, just don’t need to brick the device:

If you do have time to just try a high-rate ping to the Ethernet adapter with a recent OpenWRT/LEDE installed, that would tell me something:

sudo ping -c 5000 -i 0.001 nsm5

If it reproduces, you’ll see isochronous spikes of either 20 or 40ms around once every 900-1000ms. Might be easier to see if you add preload with “-l 100”, but you would see them either way. If you don’t have time, no sweat… :)