I have looked quite a bit for my problem, and perhaps a fix to my problem and I have never been able to find one. I've tried Microsoft fix-its, they do not work.
Basically my problem is at random times, my headset will just stop working and it will switch back to my laptop, as if my headphones are not even plugged in. It happens multiple times a day, seemingly at random (lately its been this way, but I have had it go longer than a day without doing this to me). As I am browsing the internet, as I am turning on a game, when I am away and the computer is just sitting there.
I've tried checking my device manager for differences when it is working and when it is not, I've tried updating all software, I've tried setting default devices. None of it has helped.
The only thing that fixes this is logging off, or restarting the computer. This then returns it to normal.
My laptop is an HP Pavilion dv6 windows 7 home premium x64.
Headphones in question are Razor Carcharias.