Notice, don't talk to much.
Once on WGlen in the GT3 I was on a fast lap in practise while someone does not let me pass and blocking road as I was way faster than him.
As I catched him and raced 2 corners bumper to bumper with him he spun and took me out.
I just commend it with a simple "wtf" which started him to get totally mad, shouting and teaching me what is practise about and what the heck I think I am.
I replied to calm down, but dafuq people - this is sometimes worse as you experience in Counter-Strike voicechats.