I play EC and have about 5 crashes to desktop a week. I have noticed that a few minutes before the crash, some sounds become distorted. The recall sound will have a scratchy sounding portion. If I don't shut down and restart the client immediately, I will crash. The restart always fixes the problem until the next time. From the time that the distortion starts until the crash is about 5 minutes usually.
makes me think you have a problem with your DAC in your sound card. This sounds (pun intended) like a buffer not being cleared. Not sure if this is software or hardware related, but I would see if you still crash if you disable your soundcard for a while in your control panel. Had similar issues using on-board audio card trying to play multiple media players via multiple sound cards, this was caused by a faulty audio driver.
Since so many people play the EC without ever crashing, i think it has to be some hardware - software combination that causes the trouble. I, for one, have never crashed using the EC, or maybe once... I also rarely crash using the CC.
Graphic cards may not be the problem. I have often wondered about the sound card connection, since in the EC I do notice that when recalling into busy area's i hear a bunch of stacked sounds that I do not appreciate when recalling into the same area with the CC. Also, we focus heavily on the graphics demands of complex spell effects, but the sounds are also multiple and with various layers. Particularly in busy areas during EM events... and that is when a lot of people have reported crashes. I can reduce the particle and graphics aspect of the client, not sure if I can truly turn off the sound processing (i can turn the sound volume down to 0) in the client. Hence my suggestion to just disable the sound card in the control panel. Just a thought. can't test it, as I don't crash.