atcomsystems.ca/forum Forums Wiring - Telecom Carriers - Trunks & Services Security, Alarms and Paging How do I properly wire a laptop audio output to the Valcom V-9927a?

I have a Valcom V-9927a that is used with our paging and bell system and want to use a windows program to provide the bell sounds.

I see that the V-9927A has a "signal in" for audio so I am figuring I can plug my laptop audio into that.

I cut open a spare stereo extension cable so I could have one end to plug into the laptop and the other end to wire with..

Which wire goes to which terminal of the two offered for signal in?