[Alsa-user] Half sampling rate with hdsp9632

[Andreas U. T. <and...@we...>]

Hello,

I am trying to get a Hammerfall HDSP 9632 card to work under
Linux. So far, I got success - however, whenever I record
anything, it appears the sampling rate that is used to record is
actually half the sampling rate specified.

For example, 

 arecord -d 2 -D hdsp_adat -f S16_LE -c 2 -r 48000 output.wav

should record two seconds at 48 kHz. However, the command takes
four (wallclock) seconds to complete, and produces a wave file
which sounds "too high-pitched". Editing the wave header to
change the sampling rate to 24 kHz results in a sample with the
correct pitch.

This happens when recording from analog or ADAT input.

Playback appears to have the same problem, it takes twice as long
as it should. I must confess I have not yet gotten any actual
sound from the card, but that's a second priority - the purpose
of the card is recording.


Changing the card to "Hi speed" mode and recording at 96 kHz
appears to produce a sample that's really 48 kHz.


I'm running Debian Etch with the 2.6.18-5-amd64 kernel on an
AMD64 system (Intel Pentium D CPU at 3.00 GHz). The same symptoms
appear though when I boot an i386 Kernel - I've tested this with
Knoppix 5.1 and its 2.6.19 kernel.


my .asoundrc is:
pcm.hdsp {
           type hw
           card 1
        }

ctl.hdsp {
           type hw
           card 1
        }
pcm.hdsp_analog {
        type plug
        ttable.0.6 1
        ttable.1.7 1
        slave.pcm hdsp
}
pcm.hdsp_adat {
        type plug
        ttable.0.0 1
        ttable.1.1 1
        slave.pcm hdsp
}

(note I have to change the channel numbers for hdsp_analog when switching from
"48 kHz" to "96 kHz" mode)



Is this a known issue? Is there anything I could try, like a different 
driver version?


Thanks in advance,



-- 
Andreas Trottmann
Werft22 AG
Tel    +41 (0)56 210 91 37
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