Sound card controls for VoIP patching

Here is an updated graphic with notes showing the results of my further testing of VoIP phone patching. I found it convenient to keep both sets of controls open, side-by-side, while using my headset (connected to the PC sound card (analog) jacks. Click on the graphic below for a larger view.

In general, the Recording settings (right side of graphic) control the audio going TO the distant VoIP party, on a phone call or Skype session, for example. The Playback settings (left side) control:

• the distant party's VoIP audio going to the transmitter
• the local operator's headset microphone audio going to the transmitter
• the receiver audio going to the local headset and to the distant VoIP party

The sound cards in my older PCs use a "select" check-box in the Recording controls. Only one choice can be selected at a time. To enable passing both microphone and receiver audio to the distant VoIP party, I select one of the "mix" settings. The sound card on my newer PC has mute check-boxes in the Recording controls. In that case I could mute or unmute any devices, in the same manner as provided in the Playback controls.