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我已经实现了一个频率发生器，它将同时产生六个频率。它运作良好，但是当我调高手机音量（可能高达 50% 或更低，取决于手机）时，声音会破裂。我不知道为什么电话音量会导致这个问题......以下是我如何生成频率以及如何播放声音的部分代码。

private static double sampleRate = 44100;
private double freqOfTone; // hz
private int numSamples;
private double sample[];
public byte generatedSnd[];
private AudioTrack audioTrack;
public FrequencyGenerator(double freq, int soundInterval, int muteInterval) {
    this.freq = freq;
    this.soundInterval = soundInterval;
    this.muteInterval = muteInterval;
    this.freqOfTone = freq;
    this.numSamples = (int) (sampleRate/1000*soundInterval);
    sample = new double[this.numSamples];
    generatedSnd = new byte[2*this.numSamples];
    audioTrack = new AudioTrack(AudioManager.STREAM_MUSIC,
            (int) sampleRate, AudioFormat.CHANNEL_OUT_DEFAULT,
            AudioFormat.ENCODING_PCM_16BIT, generatedSnd.length,
            AudioTrack.MODE_STATIC);
}

void genTone() {
    // fill out the array
    for (int i = 0; i < numSamples; ++i) {
        //sine wave
        sample[i] = Math.sin(2 * Math.PI * i / (double)(sampleRate/freqOfTone));

    }

    // convert to 16 bit pcm sound array
    // assumes the sample buffer is normalised.
    int idx = 0;
    for (final double dVal : sample) {
        // scale to maximum amplitude
        final short val = (short) ((dVal * 32767));
        // in 16 bit wav PCM, first byte is the low order byte
        generatedSnd[idx++] = (byte) (val & 0x00ff);
        generatedSnd[idx++] = (byte) ((val & 0xff00) >>> 8);
    }
    }
synchronized void makeSound() {
    try {
        audioTrack.write(generatedSnd, 0, generatedSnd.length);
        switch (audioTrack.getPlayState()) {
            case AudioTrack.PLAYSTATE_PAUSED:
                audioTrack.stop();
                audioTrack.reloadStaticData();
                audioTrack.setLoopPoints(0, generatedSnd.length/4, -1);
                audioTrack.play();
                break;
            case AudioTrack.PLAYSTATE_PLAYING:
                audioTrack.stop();
                audioTrack.reloadStaticData();
                audioTrack.setLoopPoints(0, generatedSnd.length/4, -1);
                audioTrack.play();
                break;
            case AudioTrack.PLAYSTATE_STOPPED:
                audioTrack.reloadStaticData();
                audioTrack.setLoopPoints(0, generatedSnd.length/4, -1);
                audioTrack.play();
                break;
            }
    } catch(IllegalStateException e) {
        e.printStackTrace();
    }

}

另一个使用频率生成器的类

public static FrequencyGenerator fg[] = new FrequencyGenerator[6];
void genSixFrequency() {
    for(int i=0;i<6;i++) {
        fg[i] = new FrequencyGenerator(i*1060 , sound, mute);
        fg[i].genTone();

    }
}
    public void makeSixSound() {
    for(int i=0;i<6;i++) {  
        fg[i].makeSound();
    }
}

我会调用 makeSixSound() 来发出声音。然后当我调高音量时就会出现问题。有人知道这个问题吗？提前致谢。

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