I posted a solution in a similar steam thread. Copying it here im the hopes someone else cab try it:
I was able to get this fixed (for me at least). I was getting disconnected consistently at times between 5-6 minutes game time.
The fix for me was updating my router setting to increase the default TCP Session Timeout value.
This was originally set to 120.
Setting it to 240 prevents me from getting kicked out at this time.
I have tested this fairly heavily so I am certain this is not a coincidence.
I ran Fiddler and wireshark between the 5/6 minute game time.
Fiddler was showing some clientError event being sent. From that timestamp, I looked at the wireshark trace and there were some TCP Resets, and TCP retransmission attempts…
So this TCP Session Timeout setting looks to be related at least.
Hope this helps somebody.
FYI:
My router is a Huawei HG659.
My ISP is Vodafone Ireland