ICH4 gaps in sound.

I have a 

pcm0: <Intel ICH4 (82801DB)> port 0xbc40-0xbc7f,0xb800-0xb8ff mem 0xf4fff400-0xf4fff4ff,0xf4fff800-0xf4fff9ff irq 11 at device 31.5 on pci0
pcm0: <SigmaTel STAC9750/51 AC97 Codec>

in my laptop.  During sound playback I hear small gaps in the sound
output.  My sense is that they occur every second or so ... about the
size of the application buffers that are sent to the sound device.
I'm using xmms for playback.  The gaps are a pop or click in the sound
and don't seem to represent any change in the timing of the sound.

Dave.

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|David Gilbert, Independent Contractor.       | Two things can only be     |
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