Audio latency

[J.E. Dooper]

Hi, 

My sound works and when I use mplayer or xmms I don't experience 
any (noticable!) audio latency. 
In applications like doomlegacy and quakeforge I do.

I think this might be the problem:
http://lists.freebsd.org/mailman/htdig/freebsd-questions/2004-August/055314.html
Though I don't understand much about the solution...

Some useful info:  

I'm using FreeBSD5.3-STABLE. Card: nForce2 onboard sound. And I compiled
my kernel with "device sound". And I load the snd_ich.ko module.

The output of `dmesg | grep pcm` :
pcm0: <nVidia nForce2> port 0xd400-0xd47f,0xd000-0xd0ff mem 0xe7080000-0xe7080fff irq 21 at device 6.0 on pci0
pcm0: [GIANT-LOCKED]
pcm0: <Avance Logic ALC650 AC97 Codec>

The output of `cat /dev/sndstat` :
FreeBSD Audio Driver (newpcm)
Installed devices:
pcm0: <nVidia nForce2> at io 0xd000, 0xd400 irq 21 bufsz 16384 kld snd_ich (1p/1r/0v channels duplex default)

The output of `sysctl -a | grep pcm` :
hw.snd.pcm0.buffersize: 16384
hw.snd.pcm0.vchans: 0
hw.snd.pcm0.ac97rate: 48000
dev.pcm.0.%desc: nVidia nForce2
dev.pcm.0.%driver: pcm
dev.pcm.0.%location: slot=6 function=0 handle=\_SB_.PCI0.MACI
dev.pcm.0.%pnpinfo: vendor=0x10de device=0x006a subvendor=0x1695 subdevice=0x100                                                                                   0 class=0x040100
dev.pcm.0.%parent: pci0

The output of `sysctl -a | grep snd`:
hw.snd.targetirqrate: 128
hw.snd.report_soft_formats: 1
hw.snd.verbose: 1
hw.snd.unit: 0
hw.snd.maxautovchans: 0
hw.snd.pcm0.buffersize: 16384
hw.snd.pcm0.vchans: 0
hw.snd.pcm0.ac97rate: 48000

My questions are:
What could be causing this latency, and what can I do to fix this?

Regards,
Jorma