Sorry for the response spam, but our audio guy sent over the following as well:
Right click the speaker next to your clock in the bottom right.
Select 'Playback Devices'
Select your Default Device (the device with the green check mark) and hit 'Properties'
Select the 'Advanced' tab.
If 'Allow applications to take exclusive control of this device' is checked, uncheck it.
Set your Default Format to 24 bit, 48000 Hz (Studio Quality)