Heroes of Newerth

[#1]

Defense of The Ancients clone-type currently in beta phase; being produced by S2 games (makers of Savage RTS).
Currently not located in the game list and I am experiencing massive latency during peak periods (6pm-10pm), I am unsure if the ports are being caught by the traffic shaping service to cope for peak traffic via another game with the same ports but I cant really say for sure.
For viewing server listings and using the chat service there is no latency at all however when inside a lobby and especially during a game the latency is consistently 600+ and Pingplotter reports many packet loss for the ports that HoN uses.
Port listings;
Chatserver : 11031
Gameservers : 11235-11335
And before I forget, there are no hardware or software firewalls on my home network that are malforming the packets. Have tried setting my own machine as a DMZ, and have port forwarding rules set up for the above mentioned ports.
Most appreciated for whatever help can be offered. Thanks.

[#2]

http://community.plus.net/forum/index.php/topic,79041.msg640485.html#msg640485
use the two links in my post above and run a capture why your playing the game i think you dont  let the capture file go over 4mb as it wont attach to the incorrect traffic mangment ticket you raise here https://portal.plus.net/wizard/index.html?Ea82ChdSAqqwtYJcjZV%2Fjl8BeHfnW7og4venLcdH9IDFyRVJeEpVZrrG...
then it will take around aweek for the new sig to go live

[#3]

After installing Wireshark it seems to have highlighted that this is not just an issue with the Heroes of Newerth traffic having the incorrect field of 0x20 but has highlighted some other issue.
Using wireshark to monitor traffic for HoN and then trying with other online games as well both result in practically every outbound packet having header checksum errors. I did some quick investigation on Google regarding this since my technological understanding cant really pinpoint the source of these checksum errors but there was mention of IPv6 resulting in these errors for Wireshark. After disabling IPv6 protocols for the network connection, the header checksums are still present.
Anyone that could provide an insight as to what might actually be wrong here?
There are no hardware or software firewalls that can be causing any issues on the network - all of them are disabled upon use of wireshark for diagnostics.

[#4]

Your network card may be doing IP Checksum Offloading, so the checksum errors in Wireshark are likely not a bother.
However, if the game traffic is prioritised as 0x20, then this WILL cause latency.
B.