Live input selection from USB DAC possible?

Hello,
with volumio I can use several music sources, like NAS, USB sticks, webradio etc…
If I’d like to add another source like an USB DAC live input (i.e. TV audio signal), would that be possible?
Thanks for all hints in advance!

Why using an analog source with Volumio?
I added Icecast output to Volumio and I do only use the Icecast output to stream to all my web radios in the house.