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Issues with samplerates below 44.1kHz

hiassoft

I'm using the new 3.18 kernel (compiled from CirrusLogic git with bcmrpi_defconfig) on a RPi B+ with raspbian and noticed that playing files with samplerates below 44.1kHz still doesn't work as it should.

 

I used Audacity to generate a 10 second stereo 440Hz test tone, once using a sample rate of 44100Hz, and once using 32000Hz and saved them as WAVs (16-bit stereo).

 

Then, on the RPi I played back the 44100Hz file (using aplay) and it sounded correct. Immediately after that I played the 32000Hz file and the pitch was too low. Both files played back fine on my PC.

 

Files with 16kHz or 8kHz sample rate show the same issues.

 

so long,

 

Hias

Parents

  • i also have this problem but it is playing 24/96 file. it will not play and if i play a 16/44.1 file, the pitch will be a bit higher. i have not done any trouble shooting yet but anybody have this problem also?

  • in reply to Former Member

    I did some more tests, using 48kHz and 96kHz files (all stereo, 16bit) and there's a distinctive pattern:

     

    If I first play the 44.1kHz file and then immediately after that any of the 8/16/32/48/96kHz files, that second file is played at a lower pitch.

     

    If I wait a bit (some 5-10 seconds), play any of the 8/16/... kHz files it plays fine, the pitch is correct. But if I play the 44.1kHz file immediately after the 8/16/... kHz file the 44.1kHz file is played at a higher pitch.

  • in reply to hiassoft

    I compared the current driver with the previous (kernel 3.12) version and noticed that the FLL1 pll setup was removed from snd_rpi_wsp_config_5102_clks - which doesn't seem to be quite correct.

     

    Re-adding the FLL1 configuration (as it was in the older driver) seems to fix this issue, now switching between 44.1 and 48kHz et al seems to work - see attached patch.

     

    I'm not 100% sure if this patch is correct, it would be fine if someone from Cirrus could have a look at it.

     

    so long,

     

    Hias

    Attachments:
    fll.patch.zip
  • in reply to hiassoft

    Thanks for the patch!

     

    I have another one for you. The support for memory mapped i/o that was present in the 3.10 Wolfson kernel disappeared in 3.12 and is still absent in 3.18.

    Jack and some ALSA plugins don't work without mmap.

    --

    Ragnar

    Attachments:
    cirrus_mmap.patch.zip
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