Subject: Re: kern/23803: audio device dies (cmpci)
To: Wolfgang S. Rupprecht <>
From: Thomas Klausner <>
List: netbsd-bugs
Date: 12/19/2003 20:36:16
On Fri, Dec 19, 2003 at 11:31:49AM -0800, Wolfgang S. Rupprecht wrote:
> (Thomas Klausner) writes:
> > On Fri, Dec 19, 2003 at 06:44:19PM -0000, Christian Biere wrote:
> >> >Synopsis:       audio device dies (cmpci)
> >
> > It doesn't die for me (1.6ZF) so far, but it stutters.
> > [Not really stutters, but it's some weird some. Perhaps
> > crackles.]
> > That happens after some minutes of watching stuff in mplayer,
> > not always the same time.
> > Pausing and unpausing (which makes mplayer close and open
> > the audio device) makes it work again.
> Same thing with my cmpci (C-Media Electronics, Inc. CMI8738/C3DX PCI
> Audio Device (rev. 0x10)).

For the record, mine is
C-Media Electronics, Inc. CMI8738/C3DX PCI Audio Device (rev. 0x10)
the same, it seems.

> It appears to happen more when I stream from another card across the
> local net.  (I abuse two computers so that I get a copy of the radio's
> audio moved from the living room to the office.)  When playing locally
> stored mp3's I hardly ever notice a problem.  When playing a dvd in
> mplayer I'll notice a problem every few minutes.

I'm not streaming over the web, but I mostly read the mplayer
data from
viaide0 at pci0 dev 17 function 1
viaide0: VIA Technologies VT8233 ATA100 controller
viaide0: bus-master DMA support present
viaide0: primary channel configured to compatibility mode
viaide0: primary channel interrupting at irq 14
atabus2 at viaide0 channel 0
wd1 at atabus2 drive 0: <ST3120024A>

that's also on the main board, like the sound "card" :)

> My guess was that it was related to underflows.  An underflow would
> trigger it and then the sound would stutter for a long time after
> that.  It is highly likely that when I stream the audio from one card
> to the other that the two cards are clocking at a slightly different
> speed.  If the recording card is clocking a very small amount slower,
> I'll eventually run out of samples to play.

Hm, not sure about that, but the hard disk, CPU and video card are
definitely up to the task.