[LAU] [Fwd: Re: xruns on ubuntu w edirol FA101]

[Jeremy Jongepier]

Weird, somehow my message did not make it?

Best,

Jeremy

-------- Original Message --------
Subject: Re: [LAU] xruns on ubuntu w edirol FA101
Date: Fri, 04 Jun 2010 18:06:27 +0200
From: Jeremy <jeremy at autostatic.com>
To: linux-audio-user at lists.linuxaudio.org
References: <4C092284.6090807 at email.dk>

Atte André Jensen wrote:
> Hi
> 
> A friend of mine has just installed ubuntu with a little phone support 
> from me. The changes we did were:
> 
> 1) Add him to the audio group /etc/udev/rules.d/40-permissions.rules
> 2) Add the following to
> KERNEL=="raw1394",                      GROUP="audio"
> KERNEL=="dv1394*",                      GROUP="audio"
> KERNEL=="video1394*",                   GROUP="audio"
> 3) Install a realtime kernel
> 
> However he still reports that jack exits after about 10s with buffersize 
> 128 and he get's lots of xruns on larger buffer settings (I think even 
> on 1024).
> 
> This surprises me, since I run standard ubuntu (recently installed the 
> realtime kernel, though) with no xruns on buffersize 128 with an FA66.
> 
> Is there anything I forgot in my over-the-phone instructions? Other 
> ideas on how to narrow this down?
> 
> NB: I don't his computer, but according to him, it's an "old laptop"...
> 

Hello Atte,

First thing that pops up in my mind is CPU frequency scaling (disabling
the Ondemand service), but apparently it's an old laptop so maybe it
doesn't apply.
And Firewire can be very picky when it's an onboard Firewire chipset. If
so it could share an IRQ and then you most probably have to use rtirq to
get it running in a stable way.

Best,

Jeremy