Softcomm seems to have gone out of business years ago. I have a Softcomm ATC-4PS four-place stereo intercom in my M4 but it had only ever been wired for the pilot & copilot intercom/jacks. I want to add the wiring for rear-seat jacks but I do not have the pinout diagram/labeling to know which jack wire connects to which intercom connector pin. Does anyone have the pinout for this intercom?

Hi Wingman,
This might meet your requirements.
Text on the 'Panel Mount Intercom' indicates the two,four and six place versions.

Excellent! Thanks very much onfinal!!