Java Sound API，没有错误但没有听到任何声音

Question

我正在尝试使用以下代码播放声音输入设备的输入。当我使用此代码时，为了获取默认系统设备，我会听到来自计算机麦克风的播放：

        DataLine.Info info = new DataLine.Info(TargetDataLine.class, format);
        microphone = (TargetDataLine) AudioSystem.getLine(info);
        microphone.open(format);

但是，我希望能够选择一个特定的输入设备，我可以使用以下代码：

        microphone = (TargetDataLine) getLine("iTrack Solo");
        microphone.open(format);

我做错了吗？这是完整的代码，包括getLine（）方法：

public static void main(String[] args) {

    AudioFormat format = new AudioFormat(8000.0f, 16, 1, true, true);
    TargetDataLine microphone;
    SourceDataLine speakers;
    try {
        microphone = (TargetDataLine) getLine("iTrack Solo");
        microphone.open(format);

        int numBytesRead;
        int CHUNK_SIZE = 1024;
        byte[] data = new byte[microphone.getBufferSize() / 5];
        microphone.start();

        int bytesRead = 0;
        DataLine.Info dataLineInfo = new DataLine.Info(SourceDataLine.class, format);
        speakers = (SourceDataLine) AudioSystem.getLine(dataLineInfo);
        speakers.open(format);
        speakers.start();
        while (bytesRead < 100000) {
            numBytesRead = microphone.read(data, 0, CHUNK_SIZE);
            bytesRead += numBytesRead;
            speakers.write(data, 0, numBytesRead);
        }
        speakers.drain();
        speakers.close();
        microphone.close();
    } catch (LineUnavailableException e) {
        e.printStackTrace();
    }

}

private static Line getLine(String name) {
    try {
        Mixer.Info[] mixerInfos = AudioSystem.getMixerInfo();
        for (Mixer.Info info : mixerInfos) {
            Mixer m = AudioSystem.getMixer(info);
            if (info.getName().equals(name)) {
                Line.Info[] lineInfos = m.getTargetLineInfo();
                for (Line.Info lineInfo : lineInfos) {
                    return m.getLine(lineInfo);
                }
            }
        }
    } catch (Exception e) {
        e.printStackTrace();
    }
    return null;
}