Tried ping between computer's static IP's connected by router (General failure).
Therefore UDP direct connection attempts went nowhere.
Tried using ffplay and pulse to stream audio, but Debian 8 is finicky with PulseAudio.
AlsaMixer displays that there is an analog audio device, and the sound works, and the device is Pulse.
Most pactl arguments return "Connection refused, Access Denied."
Tried setting default sink in system.pa and default.pa to HDMI source but the
pactl list sinks shows HDMI is Suspended.
It turns out I have a capture card in the system I want to get audio to, but the HDMI is "unplugged" in pavucontrol. An AMD and NVIDIA GPU were tried.
If I were to get networking going between the two computers, since the configuration is wired LAN, going back to streaming audio as the solution would be effective. That or perhaps getting the HDMI capture card to capture audio, as it does capture video. Rather, a different Linux distro entirely.