As far as I can tell, it happens every time I play.
UPDATE: it happens just after a match finishes, while the timer is counting down for the next one. At that point, from then on, the friends list is inaccessible. Doesn't matter if I go back to the main menu or not.
Severity: 5 (happens every time)
System specs:
Windows 7 Home Premium (64-bit)
16 gb DDR5 RAM (@ 2133 mhz)
NVidia GeForce GTX 560
[cable modem]
[Linksys router]
Let me know if I should be more specific with something and I can reply to this.
Edited by Ace4225, November 12 2012 - 02:16 PM.