So an on-topic question:
Can anyone diagnose or explain the reason for my TF2 crashing? This happens in no other game but TF2. It's been happening for a while, but more frequently of late. I will play for 30-90 mins before everything freezes and sound begins looping in my headset. No waiting helps. The PC must be rebooted.

(1) I'm the only user logged in, with nothing running but TF2. Really, nothing. No Firefox. I even turned off my AV -- ONCE -- to see if that helped.
(2) I've made exceptions for TF2 in my AV scanner.
(3) I tuned my video settings down. My FPS wanders from 25 to 50, depending on exactly what's happening. It's playable, no question.
(4) I even re-installed TF2 today.

I'm lost.