Skip site navigation (1)Skip section navigation (2)
Date:      Mon, 24 May 2004 16:16:52 -0400
From:      Andrew Kilpatrick <andrew@capybara.org>
To:        freebsd-questions@freebsd.org
Subject:   Sounds breaks up with 5.2-STABLE
Message-ID:  <200405241615.51890.andrew@capybara.org.org>

next in thread | raw e-mail | index | archive | help
Hi,

I'm using FreeBSD 5.2-STABLE on my workstation and have just installed
a CMedia CMI8738-based sound card. The card has worked well under
OpenBSD in the past (even 3 in the same machine!) but with FreeBSD
the sound breaks up and is choppy if I do specific things in X like:

- opening new windows
- dragging a window
- scrolling in my browser
- holding down a key (like space)

It sounds like the buffers are underrunning. Looking at /dev/sndstat with
verbose set to 3 reveals a lot of buffer underruns, but it doesn't seem to
notice them all. I've tried unsuccessfully setting the hw.snd.pcm0.buffersize
variable higher than 16384, but to no avail.

My system is a Mini-ITX EPIA 533MHz board with a CMI8738-based
card. Top shows lots of CPU idling. I wrote a little program in C to open
the sound card and dump stdin to it, so I can see how fast it's consuming
buffers and fiddle with the ioctls and stuff, but nothing I do seems to make
it work, and writing buffers larger than 16384 makes it play with gaps
between buffers.

That's what I've tried so far... any help would be greatly appreciated!


Cheers,

Andrew



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200405241615.51890.andrew>