When connected to two networks, can I tell my iMac to use a specific network for a certain application?

Solution 1:

Well, I got a great answer from the Audiofusion team. It resolves my specific situation.

Per Audiofusion:

SoundCaster will only send audio over the Ethernet connection. Just make sure the WiFi connection is listed first and the Ethernet connection is listed second in your Network Preferences.

Thanks!