I set up Syncthing for my dad a few weeks ago, between his PC and his laptop. At first the sync was incredibly slow, and it turned out Windows on both machines

I set up Syncthing for my dad a few weeks ago, between his PC and his laptop. At first the sync was incredibly slow, and it turned out Windows on both machines though the local network was a public one, so they weren't talking directly to each other but through a relay out on the internet. I fixed that and it got 15-20 times faster. Maybe you have the same problem?