The issue is "Exclusive Mode."
Right-click on the white speaker icon located in the system tray on the Windows task bar near the clock.
Choose Playback Devices
Select the audio device that you would like to adjust (i.e. - AudioBox, FireStudio)
Click Properties
Choose the Advanced tab
Uncheck the Allow applications to take exclusive control of this device box (both boxes will be disabled now)
Click OK
Hopefully that should fix the problem.