音量调节

    1. alsamixer

    噪音问题

    1. sudo nano /boot/config.txt

    底部增加

    1. audio_pwm_mode = 2

    如果使用了USB声卡：

    列出声卡

    1. sudo aplay -l

    card 1: Device [USB Audio Device]即是USB声卡。

    1. **** List of PLAYBACK Hardware Devices ****
    2. card 0: ALSA [bcm2835 ALSA], device 0: bcm2835 ALSA [bcm2835 ALSA]
    3.   Subdevices: 7/7
    4.   Subdevice #0: subdevice #0
    5.   Subdevice #1: subdevice #1
    6.   Subdevice #2: subdevice #2
    7.   Subdevice #3: subdevice #3
    8.   Subdevice #4: subdevice #4
    9.   Subdevice #5: subdevice #5
    10.   Subdevice #6: subdevice #6
    11. card 0: ALSA [bcm2835 ALSA], device 1: bcm2835 IEC958/HDMI [bcm2835 IEC958/HDMI]
    12.   Subdevices: 1/1
    13.   Subdevice #0: subdevice #0
    14. card 1: Device [USB Audio Device], device 0: USB Audio [USB Audio]
    15.   Subdevices: 1/1
    16.   Subdevice #0: subdevice #0


    设置USB声卡为默认声卡

    1. sudo nano /etc/asound.conf

    输入如下内容

    1. defaults.ctl.card 1 
    2. defaults.pcm.card 1 
    3. defaults.timer.card 1

    其他

    列出麦克风

    1. arecord -l

    card 1: Device [USB Audio Device]即是USB麦克风。

    1. **** List of CAPTURE Hardware Devices ****
    2. card 1: Device [USB Audio Device], device 0: USB Audio [USB Audio]
    3.   Subdevices: 1/1
    4.   Subdevice #0: subdevice #0

    测试USB声卡

    1. speaker-test -Dplughw:CARD=Device -c2 -twav

    录音测试

    1. arecord -Dplughw:CARD=Device -fcd -c2 -twav test.wav

    播放录音

    1. aplay -Dplughw:CARD=Device test.wav