Hi Karl
Interesting.
The trigger for this was possibly the DHCP lease on the PC expiring and failing to renew.
Cycling the wifi on the phone likely did not cause a lease renewal as its lease was still current.
So you have a Linux Mint PC trying to get a DHCP renewal from the DHCP server on the gateway node, via the satellite node and across the batman-adv mesh.
What is interesting is that cycling the satellite node seems to have fixed the issue.
But I wonder if rebooting the PC might have had the same effect (ie not just cycling its network port on and off, but restarting all networking on the PC)
If you want to test whether DHCP is the underlying issue, you could try setting the DHCP lease to a much shorter value than the 7200 second default value so that it renews, say, every five minutes, then run the movie and see what happens.
It might also be interesting to watch the RAM memory usage on the various nodes during heavy network usage. The 32MB RAM on the WR841 may be getting pushed pretty hard during heavy streaming on the network.
Note that the SECN firmware is just a bunch of shell scripts that set up the configuration of OpenWrt, Batman-adv and the various other packages. It does nothing at run time except run a script every ten seconds to update the status page data.
So you need to look at the behaviour of the underlying software components for these sorts of run time issues.
Regards
Terry