Audio only works for certain applications

Hi everyone, first time stumbling across a Windows problem I couldn't solve myself. The issue I am having is that audio will only play through specific applications. It will work in WMP and at certain times in video games (in the main game itself but not the intro movies or voice chat, can hear but not talk), both speakers and usb headset work in skype both sending and receiving audio. However nothing comes up in Firefox as well as windows login/system sounds do not play.

I've tried uninstalling the devices and reinstalling via Device Manager -> Sound, video and game controllers. I've added a second sound card which also has the same problem. I've downloaded and installed device drivers manually. I of course started by playing with the audio settings via Playback Devices/Volume Control Options. Audio per application is not muted as Firefox is never even shown in the volume mixer even with youtube open with a video with sound (have tried multiple other sites as well, none work). I've also gone so far as to re-seat the connections on my mother board but have as of yet found nothing, hardware, software or configuration wise that solves this problem. Any assistance would be greatly appreciated.

Would i be correct in assuming that its only video files that are currently inaudible?

If so re install video codecs and maybe graphics card drivers?

Well no its not only videos. Its also in game voice chat. I've tried uninstalling and reinstalling flash but this does not fix the problem. Graphics drivers deal with video not audio but I went ahead and did it anyways, no change.

Reinstalled Windows. Problem solved.