services/audiopolicy/config/stub_audio_policy_configuration.xml

<?xml version="1.0" encoding="UTF-8"?>
<!-- Copyright (C) 2017 The Android Open Source Project

     Licensed under the Apache License, Version 2.0 (the "License");
     you may not use this file except in compliance with the License.
     You may obtain a copy of the License at

          http://www.apache.org/licenses/LICENSE-2.0

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     distributed under the License is distributed on an "AS IS" BASIS,
     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     See the License for the specific language governing permissions and
     limitations under the License.
-->

<module name="stub" halVersion="2.0">
  <attachedDevices>
    <item>Default Out</item>
    <item>Default In</item>
  </attachedDevices>
  <defaultOutputDevice>Default Out</defaultOutputDevice>
  <mixPorts>
    <mixPort name="stub output" role="source" flags="AUDIO_OUTPUT_FLAG_PRIMARY">
      <profile name="" format="AUDIO_FORMAT_PCM_16_BIT"
               samplingRates="48000" channelMasks="AUDIO_CHANNEL_OUT_STEREO"/>
    </mixPort>

    <mixPort name="stub input" role="sink">
      <profile name="" format="AUDIO_FORMAT_PCM_16_BIT"
               samplingRates="48000" channelMasks="AUDIO_CHANNEL_IN_STEREO"/>
    </mixPort>
  </mixPorts>
  <devicePorts>
    <devicePort tagName="Default Out" type="AUDIO_DEVICE_OUT_STUB" role="sink">
    </devicePort>

    <devicePort tagName="Default In" type="AUDIO_DEVICE_IN_STUB" role="source">
    </devicePort>
  </devicePorts>
  <routes>
    <route type="mix" sink="Default Out" sources="stub output"/>

    <route type="mix" sink="stub input" sources="Default In"/>
  </routes>
</module>