Usb mic device can change the sampling rate?

Robotics & Edge Computing Jetson & Embedded Systems Jetson TX2
1

Usb mic device can change the sampling rate?
The default should be 48000
I set the instruction to 44100 The following warning appears

nvidia@tegra-ubuntu:~$ arecord -f S16_LE -c 1 -r 44100 -d 20 -Dhw:2,0 test12.wavxcb_connection_has_error() returned true
Recording WAVE 'test12.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Mono
Warning: rate is not accurate (requested = 44100Hz, got = 48000Hz)
         please, try the plug plugin

Where should it be modified?

2

Hello!

I believe that this means that your usb device does not support 44100kHz.

What do you see under the directory ‘/proc/asound/card2/’?

For example, when I connect my usb speaker I have …

$ ls /proc/asound/card2/
id        pcm0p/    stream0   usbbus    usbid     usbmixer

And …

$ cat /proc/asound/card2/stream0 
C-Media INC. Audio Advantage MicroII at usb-0000:00:14.0-2, full speed : USB Audio

Playback:
  Status: Stop
  Interface 1
    Altset 1
    Format: S16_LE
    Channels: 2
    Endpoint: 6 OUT (ADAPTIVE)
    Rates: 44100, 48000

Hence, you can see that my speaker supports 44.1kHz and 48kHz.

Regards
Jon

3

Strangely enough, I can record on cudacity at 44100 frequency and the sound is normal.

cudacity.png
cudacity.png1112×787 99.9 KB

4

Any chance it is being sample rate converted? Again please check the supported sampling rates for the USB device.

Regards,
Jon

5

Upload audacity image in attachment

root@tegra-ubuntu:~# cat /proc/asound/card2/stream0
iTalk-02 at usb-3530000.xhci-2, full speed : USB Audio

Capture:
  Status: Stop
  Interface 1
    Altset 1
    Format: S16_LE
    Channels: 1
    Endpoint: 2 IN (ASYNC)
    Rates: 48000
6

Thanks. So the USB Mic only supports 48kHz and hence the message you are seeing above. Audacity is most likely sample rate converting from 48kHz and you can select the recorded sample rate via the ‘project rate’ setting in audacity.

Regards,
Jon