I would like to be able to play an audio recording over an open phone conversation. I.e., while the phone is connected (an outgoing call) a prerecorded audio file is played over the open phone connection. How can I do this?
If you have a phone or secondary device that you can play the audio file on and both devices have auxillary ports, simply buy a cheap aux cable, cut it open, and plug both wires in the other way, so the phone thinks that the other device is a microphone. This works better that simply playing it through a speaker because there is much more clarity and no background noise.