Avast blocks randomly alle new Internet connections

Hey, i have a Problem with AVAST, since i upgraded to Internet Security

After some time of use, AVAST starts to block ALL new connections.

Means, Youtube stops loading, twitch too, but if im in a League of Legends game, oron a TS³ Server, it still works. But if im disconnecting and try again, it fails too. WOrkaround is to deactivate all modules and start them right after again. Pretty annoying.

Any solutions?

Check your Firewall settings: ( Private or Public )
https://www.avast.com/en-eu/faq.php?article=AVKB25

I even removed the Firewall completely for a few days,it still happened the same. So i guess, its not the Firewall directly