public Builder mergeStreamingAudioConfig(
        com.google.cloud.texttospeech.v1beta1.StreamingAudioConfig value) {
      if (streamingAudioConfigBuilder_ == null) {
        if (((bitField0_ & 0x00000002) != 0)
            && streamingAudioConfig_ != null
            && streamingAudioConfig_
                != com.google.cloud.texttospeech.v1beta1.StreamingAudioConfig
                    .getDefaultInstance()) {
          getStreamingAudioConfigBuilder().mergeFrom(value);
        } else {
          streamingAudioConfig_ = value;
        }
      } else {
        streamingAudioConfigBuilder_.mergeFrom(value);
      }
      if (streamingAudioConfig_ != null) {
        bitField0_ |= 0x00000002;
        onChanged();
      }
      return this;
    }
<pre>
Optional. The configuration of the synthesized audio.
</pre>

<code>
.google.cloud.texttospeech.v1beta1.StreamingAudioConfig streaming_audio_config = 4 [(.google.api.field_behavior) = OPTIONAL];
</code>
java-texttospeech/proto-google-cloud-texttospeech-v1beta1/src/main/java/com/google/cloud/texttospeech/v1beta1/StreamingSynthesizeConfig.java