Headphone problems

This is normal. Happens to me when I switch from speakers to headphones or vice versa. The sound settings prior to you loading the game were configured a specific way based on what you're using. When you change the method of output mid-game, you will need to close the program and reload it to use the method of output of your choice. This is self-explanatory in the sense that each piece of hardware is configured a specific way, if you change the method of hardware, you will need to change the settings as well. Unfortunately, in this case, the only way to change the settings when you switch between the two is to close Crossfire and reload it. Back in the old days, you actually had to reboot your computer in order for the computer to recognize the hardware that you switched over to. Fortunately for us, all that is required is reloading a program.

You said that you're not pulling out the mic cord and, I'm assuming, you believe that the headset is still plugged in. However, the headset is not registered as "working" or not recognized by the computer simply because you didn't put in the essential component: the headset plugin. Therefore, the sound settings are not configured for your headset, only your speakers. In addition, I've never been able to plug in headphones and my speakers simultaneously, my computer makes me choose one so that it can adjust the settings appropriately.

It's not that it doesn't happen with other programs because it does. Sometimes it happens with my media player or videos; like Taco Bell said, it's just the way it is.