Java uses SourceDataLine to play audio slowly (the tone will be dull)

 /**
     * 慢速播放( 音调变沉闷 )
     * @param ais
     * @param player
     * @throws IOException
     */
    private static void handleCase2_slow_muffled(AudioInputStream ais, SourceDataLine player ) throws IOException {
        System.out.println( "case2:" );
        int len;
        byte[] buf = new byte[4];
        int i=0;
        long t = System.currentTimeMillis();
        SimpleDateFormat sdf = new SimpleDateFormat("HH:mm:ss");
        while((len=ais.read(buf))!=-1) {
            i++;
            if( i < 2152526 ){
                continue;
            }
            if( i >= 3360000 ){
                break;
            }
            // 实现变慢，但是调不变粗
            //左声道
            buf[1] = ( byte ) ( buf[1] );
            //右声道
            buf[3] = ( byte ) ( buf[3] );
            player.write(buf, 0, len);
            if( i % 2 == 0 ){
                //左声道
                buf[1] = 0;
                //右声道
                buf[3] = 0;
                player.write(buf, 0, len);
            }
        }
    }

The principle is to play a sample and fill a 0 sample (the purpose of filling is to slow down the playback speed). When the sound is slowed down, the timbre also changes and becomes very dull, like a monster. Generally, it is used as a monster sound effect