A pleasure! If you try mjpeg-streamer, please report back how it works. As I said, I’m getting quite a lot of delay, so I’m trying to find another solution. I’ve tried this: Low Latency Raspberry Pi video transmission - Altax US Consultancy - but since I’m not using the rpi-camera, I’ve not succeeded so far — probably because I’m not good enough with the rpi and shell commands.
Oh, and by the way: I said I had som trouble with the dual pair of Fathom X-networking boards not wanting to talk via the same switch: I found this thread which helped with that: Dual Fathom-X Crosstalk
The solution was to have just one Fathom X-board receiving the data from two boards: i.e. two Fathom X-boards in the ROV talking over the same single twisted pair can be read by a single Fathom X-board topside. I didn’t know that.