TMM with computers on the same connection

Was queuing up for 4v4 TMM, 2 computers using the same internet connection, one of us showed 7/8 connected, the other showed 1/8 connected. We've managed 4v4 TMM games before (although usually after many attempts).
I'm assuming given what was displayed that it was one of our computers failing to connect, but seemed strange that one could connect to everyone else while the other couldn't even connect to the computer on the same internet connection so thought I'd mention in case it might be a wider issue than just with one of our computers.