Looks like there is some success dealing with looping sound crash by manually setting your pagepool size in the registry. Some people on steamforums reported this fixed their crashing problems. Seems like the majority of the problems are a memory issue and TF2/Source games are taking up more paged pool memory than it is supposed to, this is also why some people reported success when uninstalling their anti-virus, since it apparently frees up paged pool memort
NOTE: This tweak can seriously screw up your system if your don’t know what you are doing.
Here’s how you open Registry Editor:
Start Menu > Run > regedit
Surf down to this key. The REG_DWORD "PagedPoolSize"
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management
Double click on "PagedPoolSize". Hexadecimal is listed first. Change the "Value Data" to one of these below:
Note: You only need to enter EITHER Hexadecimal or Decimal. They both are the same.
Megabytes Hexadecimal Decimal
192Mb 0c000000 201326592
256Mb 10000000 268435456
384Mb 18000000 402653184
You do not need anything bigger than 400Mb… in most cases 300Mb is too much as well.
Once you are done, make sure you reboot your computer.
Enjoy!