Ability to select input/output devices

[LJWatson]

It seems that the application defaults to the default soundcard on the system. For machines with multiple audio input/output devices, it would be useful to be able to choose which one you want to use.

I use a screen reader through a headset that behaves like its own soundcard. I have music etc. playing through the default soundcard through desktop speakers. Using the WebEx RTC interface, I don't seem to be able to choose to use my headset as the input/output device (without setting it as the default at the OS level).