android call can play audio files, please?

For example, a call, a voice program put in place of the call. Computer speakers to play the file, and then the phone's microphone in front of the speaker, can be achieved. But this approach seems too awkward.<-! Main posts under Banner (D4) -><-! Posts under the main text (D5) ->
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You want this in your own voice call app in? Then be key to achieve?

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To ensure that each mobile phone can receive your voice software packages, like micro-channel bit. You can talk. You can leave a message.
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Yes, there is not the kind of call background sound software it.