Left 4 Dead 2 Crashes with sound loop (ctrl+alt+del lets me go back to the desktop).

[lil pussy boy]

OK so my L4D2 is crashing, I have tried every single fix there is out there, disabled the steam overlay, run with -nosound, run on -dxlevel80 -medium, increased paging file size, changed the pagespoolsize in the registry, disabled multicore support, run a clean boot, run windowed, deleted the client.dll and redownloaded it, pretty much every.

I'm at a ♥♥♥♥ing loss, this shouldn't be happening, also not only does this effect L4D2, it effects every source game, I can play for about 15mins or so and then d-d-d-d-d-d etc. Now I'm playing this on a laptop but it's a brand new laptop with nvidia GTX 670M graphics (alongside Intel HD 4000 with optimus), intel i7-3610 processor, 8GB ram. It can play Deus Ex: Human Revolution, Fallout 3 etc. on full specs without any sort of problem. WTF is the problem with source games? I've been waiting to play me some L4D2 for ages as well as Portal 2 and it's making these games impossible to play. There must be some solution out there!

[lil pussy boy]

OK. Progress. Tried verifying local cache and it found one file (specifically client.dll) was missing (or more correctly corrupted I guess) suggesting that it's a problem with the source engine itself rather than local hardware etc. letting steam redownload this allowed me a play through of Dead Centre offline (although that was only for 1/2 an hour and afterwards when I got it to verify the cache again sure enough it decided it needed to redownload client.dll again). This also happened in CS:GO which kept crashing. It would be nice if someone from valve could have a look into this as I'm pretty sure I'm not the only one facing this problem.

I'm now reinstalling both L4D2 and CS:GO but I don't have much faith in this solving the problem (as it seems it hasn't really helped other people suffering the same issue).

[lil pussy boy]

OK, had a look and I think I've discovered the problem (which fits with games working fine without an internet connection): It's CEG crashing the game on purpose (http://forums.steampowered.com/forums/showthread.php?t=1860006&page=2). FFS I've bought these ♥♥♥♥ing games and I expect to be able to play them without them being crashed ON PURPOSE by trigger happy DRM. Valve, can you ♥♥♥♥ing sort it out?

[kaixa]

well... same with me when i click the "addons" button on main menu -.-"