Yes, disabling the autoscroll on the middle mouse click button is what I'm trying to do. I'm using this key to speak on mumble hence why it's really annoying.
However, I tried this solution and it does not seems to work.
What I did is in a singleplayer game (tutorial stuff) pressed enter :
say:/set MouseDragScrollThreshold -1
Then enter.
Then tried to use middle mouse button.
And I still have the autoscroll :
(don't look at my failed try of using the command, I did right after, without the :a)
Any other idea to help :s ?