|OK for anyone interested; i fixed the problem..|
Turns out this has been a barely noticed problem which has been around since the release of Vista, and continued by Win 7, both OS's have a service called "Multimedia Class Scheduler" or "MMSCC"
Aparently this service seems to handle CPU priority issues when playing back multimedia, but also seems to do something to high packet receive rates in a network, drastically slowing them down, mostly noticed when transferring files via LAN or putting trough high bandwidth on few connections, like usenet...
As expected, turning off MMSCC fixes the problem i had..
This is how to turn it off:
Open regedit and go to:
On the right plane double click "DependOnService" and only delete "MMSCC" from the key
The above is to stop mediaplayback being dependend on MMSCC to work
Now just stop "Multimedia Class Scheduler" in services (start, run, "services.msc") and also disable startup of the service, when disabling the MMSCC service, music might stop working, but will return after reboot.
Intel Q6600 @ 3GHz
Asus P5N-T Deluxe
4GB OCZ DDR2 1000
eVGA GeForce GTX 285
WD Velociraptor 150GB,
2x 320GB,16MB in Raid0
Tagan Piperock 1100W