audio skipping/pure sound quality

Richard Ryniker ryniker at
Tue Jan 18 17:58:00 UTC 2011

I have experienced effects like those you described when Pulseaudio (or
perhaps something else in the audio-processing chain) must do sample-rate
conversion, such as from 44.1 KHz to 48KHz, to drive my USB speakers.

Sox has been an effective solution for me.  Try "play" (a link to sox that
denotes output to sound hardware instead of a file) to learn whether sox
may offer superior sample-rate conversion that avoids the problems you

There are probably a handful of tools that will display information
about sound devices.  Audacity has a convenient one:

    Help -> Audio Device Info

that displays supported sample rates.  For example, I see:

    Default capture device number: 13
    Default playback device number: 13
    Device ID: 0
    Device name: ALSA: Bose USB Audio: USB Audio (hw:0,0)
    Input channels: 0
    Output channels: 6
    Low Input Latency: -1.000000
    Low Output Latency: 0.010667
    High Input Latency: -1.000000
    High Output Latency: 0.042667
    Supported Rates:

Output like this may display a needed sample rate for your USB sound
device (48000 in my case).  If you use sox to convert a file to the
target rate before you play it, and it then sounds good, this confirms
the problem involves resampling.

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