Hello,
actually it is not really important which sound card one uses.
All you have to do (on windows at least… don’t really know if this can be done on OSX) is to open the Windows Control Panel, click on “Sound”, select your default device on Playback and click on Properties. Under “advanced” remove the check from the option “Allow applications to take exclusive control of this device” and that’s it.
Then you will be able to have
2 televisions on
quoting airflamesred.
Regards