Benway's Test Cam With Audio.
The final version will have no popups. In the meantime, if you have a popup killer, it's advisable that you enable it.

Cam Control
Refresh Webcam - No Cam (For Smoother Audio)
Audio Control
Click 'LoFi Audio' or 'HiFi Audio' to start audio.
LoFi Audio - HiFi Audio - Disable Audio
If Audio stops, click 'Disable Audio' and then 'LoFi Audio' or 'HiFi Audio'.
If switching between LoFi and HiFi audio streams, it works better if you select 'Disable Audio' first.