Now, after some time i have the problems again.
I use Openlitespeed without directadmin.
A simple restart don't help but i have many warnings in the server logfile.
Same problem here with version 1.7.6.
Sometimes it is working but after some time it stop working.
The Quic Header is missing in http responses, but i can connect with netcat.
I use Wordpress with openlitespeed caching.