Recently I’ve had this issue with teamviewer where when I would connect to a machine, network access would just stop for about 20-30 seconds. (Very annoying to say the least.)

I checked in the options, no proxy, no special network settings, so wasn’t exactly sure what was going on.
Still, I have no idea what was going on but I disabled IPv6 on my network card, reopened teamviewer and the connections seem to go through as normal.

Weird. If something else changes I’ll report back, but hopefully it’s fixed now.