private com.google.protobuf.SingleFieldBuilderV3<
              com.google.protobuf.Duration,
              com.google.protobuf.Duration.Builder,
              com.google.protobuf.DurationOrBuilder>
          getSpeechStartTimeoutFieldBuilder() {
        if (speechStartTimeoutBuilder_ == null) {
          speechStartTimeoutBuilder_ =
              new com.google.protobuf.SingleFieldBuilderV3<
                  com.google.protobuf.Duration,
                  com.google.protobuf.Duration.Builder,
                  com.google.protobuf.DurationOrBuilder>(
                  getSpeechStartTimeout(), getParentForChildren(), isClean());
          speechStartTimeout_ = null;
        }
        return speechStartTimeoutBuilder_;
      }
<pre>
Duration to timeout the stream if no speech begins.
</pre>

<code>.google.protobuf.Duration speech_start_timeout = 1;</code>
java-speech/proto-google-cloud-speech-v1/src/main/java/com/google/cloud/speech/v1/StreamingRecognitionConfig.java