So, ever since some time around December I’ve been having this issue in which starting up Gmod will cause my internet connection to crash and does not go back up until I reset my modem. It doesn’t matter if I play singleplayer or multiplayer, it always crashes after about 5 minutes. I’ve tried lowering the max pings/minute in the steam settings, I’ve tried disabling my router’s firewall protection and I’ve tried making a clean install by deleting my Gmod folder in steamapps and re downloading several times. This problem started randomly for no reason, the only possible cause I can think of is when I asked my ISP to open up to the ports in my router required for Xbox LIVE, but i’m not sure how that would affect it. Router is a Linksys E1500, i’m on an ADSL 2mb connection, and my connection is wired. Any help is appreciated in advance, please help!
EDIT: I forgot to mention other source games like TF2 and CSS don’t have this problem, it’s only Gmod that causes it.
EDIT: After browsing around a bit I discovered that using a VPN gets rid of the problem, I tried this and was able to play for an hour without any sort of problems.