[ALSA - driver 0000502]: Mp3+ crackles when on alsa, not when on oss emulation

[bugtrack@alsa-project.org]

A NOTE has been added to this issue.
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<https://bugtrack.alsa-project.org/alsa-bug/view.php?id=502> 
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Reported By:                hhg
Assigned To:                Clemens Ladisch
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Project:                    ALSA - driver
Issue ID:                   502
Category:                   USB - usb-audio
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     assigned
Distribution:               Mandrake 9.2
Kernel Version:             2.6.8
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Date Submitted:             09-15-2004 00:44 CEST
Last Modified:              08-30-2005 12:22 CEST
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Summary:                    Mp3+ crackles when on alsa, not when on oss
emulation
Description: 
this shell-cut-and-paste wil ilustrate my problem:

At first when I plug my mp3+ in, it crackles. It is not scraping or
static, it is a distinct pop in the sound about 2-3 times/sec not
rythmical. The card shows up in alsamixer -c1, and everything about
controling it works. Then, without plugging my card in or out, I do this:

[root@localhost hhg]# rmmod snd_usb_audio
[root@localhost hhg]# modprobe audio
[root@localhost hhg]# alsamixer -c1
 
alsamixer: function snd_ctl_open failed for hw:1: No such file or
directory

I also have a boult-in intel-8x0-card working fine with alsa. But now the
mp3+card works great. Using oss-emulated mixer the card can also be
controled. I have to use oss-output, though, as the card no longer is
registrered by alsa.

even if I do

[root@localhost hhg]# modprobe snd-usb-audio

alsamixer -c1 fails and the card stil works as an oss-card.
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----------------------------------------------------------------------
 hhg - 09-15-04 13:09 
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After reading a previous bug, I discovered that when I plug my mp3+
directly into my pc and not via my usb2.0-hub (sweex hub) the crackling
goes away when on alsa-driver.

This is very strange. How can alsa not send good data through the hub when
the oss-emulator (audio) can do it just fine?

----------------------------------------------------------------------
 jdthood - 08-30-05 12:22 
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Hi.  What's the status of this bug.  Any improvement in later ALSA
releases?

Issue History
Date Modified  Username       Field                    Change              
======================================================================
09-15-04 00:44 hhg            New Issue                                    
09-15-04 00:44 hhg            Distribution              => Mandrake 9.2    
09-15-04 00:44 hhg            Kernel Version            => 2.6.8           
09-15-04 13:09 hhg            Note Added: 0001760                          
08-30-05 12:22 jdthood        Note Added: 0005974                          
======================================================================




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