Call of Duty 4 single player crash to desktop

I just installed Call of Duty 4 and when I try to run the single player mode nothing happens. I just see a quick flicker on the desktop but the game doesn't launch. When I try to run it again, it gives me this message:

It appears that cod4 did not quit properly the last time it ran. Do you want to run the game in safe mode?

Multiplayer seems to work fine and when I try to switch to single player from the multiplayer menu the same thing happens, it just goes back to my desktop and that message shows up again

I had this issue on Windows Vista (yep) and I assume its on Win 7 too. Plug something into the microphone audio jack.

The following 2 actions are known to solve most issues with the game crashing:

• Enable stereo mix
• Plug in an headset/mic

Sources:

http://steamcommunity.com/app/7940/discussions/0/618453594765419915/ http://steamcommunity.com/app/7940/discussions/0/864956555036760746/