3.0 RC1 25309 Download speed problem

[Zeeu]

I lately installed Utorrent 3.0 over my existing 2.2.1 and instantly noticed dramatic reduce in overall speed. Normally my maximum download speed is around ~820kB/s, but with 3.0 I've never seen it go over ~650.

I read the speedproblem FAQ/whatever and tried changing several different connection options and ran the speed guide few times with no effects. The real problem here is that after downgrading back to 2.2.1 it started working again as it should, and thus I have no idea where the problem could be. My firewall was disabled during the test and I'm running Q6600 ~3ghz 4gb RAM and W7 64bit with Avast 6.

Here are the results of me downgrading back to 2.2.1 from 3.0 while downloading a linux distro. The sampling time is small, but the difference is clear as day and always noticeable in all torrents.

http://dl.dropbox.com/u/16684226/utorrent%20wtf.jpg

Any ideas what could cause this?

edit: Apparently I posted on wrong forum section, sorry about that.