Playing audio to telephony uplink is possible, but the microphone input data is also transmitted.

  1. How to switch off microphone on Android devices?
  2. Is there a possibility to play audio to telephony uplink while call on mute?
  • 3
    possible duplicate of How can I play an audio recording over an open phone conversation?
    – GAThrawn
    Feb 7, 2012 at 14:09
  • @GATHrawn, NO,the suggested solution is related to recording which in fact quite opposite to Answering machine feature.
    – user12295
    Feb 7, 2012 at 15:39
  • The question is about playing back a piece of pre-recorded audio over the phone conversation, which is exactly point 2 of your question. Currently the only answer (which hasn't been accepted) is giving a workaround of playing pre-recorded audio whilst letting the inbuilt microphone pick it up during a call. It's not a good solution, but it is a solution. Things may have changed since that answer was posted June, if so anyone is welcome to post another answer which the OP could accept. Disregarding any answers that question is still very, very similar to this one.
    – GAThrawn
    Feb 8, 2012 at 9:13
  • 1
    The other question isn't about recording, it's about playing "a recording", i.e., an audio file. You're right that the other question doesn't mention anything about muting the mic, though, so I think they are fine to stay separate. I'd encourage you to answer the other question, since it sounds like you've discovered how to play audio over the call without using the mic. Feb 9, 2012 at 18:06
  • 1
    Not via code. any 3rd party app or any settings on device,
    – user12295
    Feb 24, 2012 at 10:01

1 Answer 1


I have been developing my own answer machine application and hit two major stumbling blocks. One is that setMicrophoneMute(boolean on) simply doesn't work. And the other issue is playing an audio greeting down the phone line.

This isn't possible due to hardware restrictions and it doesn't even work if the microphone is switched on and the audio is played through the speakers.

  • Have you found the solution ?
    – Hunt
    Apr 9, 2012 at 17:30
  • @mark Have you found the solution?
    – Jack
    Dec 4, 2012 at 9:25
  • @Jack - it's possible, but both cases require rooted ROMs to work, thus one of them (ALSA-based) depends on Qualcomm chipsets.
    – kagali-san
    Nov 17, 2013 at 0:47
  • @Hunt, wondering what you have found in that time
    – kagali-san
    Nov 17, 2013 at 0:47
  • Are there any news?
    – red-o-alf
    Aug 23, 2015 at 20:50

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .