Modem continually sending data back to base - further information

[Phil]

I now think the culprit for the continual data stream is not the 
Nighthawk, and the data stream is mostly inward. This is happening with 
all applications closed and not just minimised. "Top" shows 1 running 
process, top itself, 1 zombie and 300 odd sleeping processes.

Also, if another laptop, also running Xubuntu 25.10, is also connected 
to the Nighthawk network only my laptop show this data flow. I'm now 
thinking that a sleeping process is somehow causing the unwanted data flow.

Yet, the data flow only occurs when my laptop is connected to the 
Nighthawk and not when I use my phone's hot-spot.

Does any of this make any sense at all?

-- 
Regards,
Phil