Subject: Re: PCM distorsion snapshots from SATA/ALSA conflict (was:
	[Alsa-user] Pb with simultaneous SATA and ALSA I/O)
From: Lee Revell <rlrevell@joe-job.com>
To: Dominique Dumont <domi.dumont@free.fr>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>,
       alsa-user <alsa-user@lists.sourceforge.net>,
       Francesco Peeters <Francesco@FamPeeters.com>,
       linux-kernel <linux-kernel@vger.kernel.org>
In-Reply-To: <878xjrqeh2.fsf_-_@gandalf.hd.free.fr>
References: <877izsp3dm.fsf@gandalf.hd.free.fr>
	 <13158.212.123.217.246.1159186633.squirrel@www.fampeeters.com>
	 <87y7rusddc.fsf@gandalf.hd.free.fr> <1160081110.2481.104.camel@mindpipe>
	 <87r6xmscif.fsf@gandalf.hd.free.fr> <1160082761.2481.106.camel@mindpipe>
	 <1160085016.1607.26.camel@localhost.localdomain>
	 <878xjrqeh2.fsf_-_@gandalf.hd.free.fr>
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Date: Sun, 08 Oct 2006 12:41:13 -0400
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(it's probably a bad idea to attach .jpgs to a LKML post - please post
them on the web and send a URL)

On Sun, 2006-10-08 at 12:38 +0200, Dominique Dumont wrote:
> Anyway, the oscilloscope shows that:
> - a spike occurs every 330 useconds (about 3kHz)
>   (note: 330us is 15.85 times the period of the 48KHz spdif stream) 
> - the spike level roughly matches the level of the sine waves 330
>   useconds sooner
> 

You seem to be using a period size of 256 samples - any change if you
use a larger period size?

Any change if you use setpci to increase LATENCY_TIMER for the SBLive!
card?

Lee

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