Android: Playing audio file though telephone line

Question

I have been searching the internet for an answer, on how to play an audio file through the telephone line (See example if you wonder what I mean). Now I have come to this site to find the answer: Is it possible to play an audio file located on your telephone, so that the caller can hear it, without turning on your speaker and let it blast it out loud? If so, does anybody know a site to look it up at?

Example: Peter calls Annie. Annie answers the call, and decides to play her favorite music to Peter, but she doesn't want to turn on her speaker, because her parents are sleeping in the room next to her.

I know that a telecommunications server is able to play music when people are on hold, waiting for an employee or in a queue, but is an Android phone able to do the same?

Answer 1

You can't do this.

All audio calls are routed through the baseband chip at a hardware level. The underlying telephony technology isn't exposed to the OS, much less the Android APIs.

So basically, this is impossible, unless you're willing to settle for playing it over the loudspeaker and hoping it gets picked up clearly.