[CLUE-Tech] ALSA sound with Gentoo?

[Matthew Porter]

Thanks to everyone who offered encourangement and advice on installing
Gentoo.  It was very helpful (and it was interesting to learn that
genkernel is both my "friend" and something I should "avoid like the
plague" -- I've known people like that...)

We installed the OS over the course of the weekend -- set something up
to run, look in on it once in a while, start up the next step, repeat.
By Sunday night we had a system with a 2.6.7 Gentoo kernel, X and
KDE running beautifully.

Now I'm almost ready to get out the Debian Sarge install disk and
start over.  I've been banging my head against a wall trying to get
sound working with ALSA.  It works fine under Knoppix, so I know the
hardware is fine, but with Gentoo, trying to play a test .wav with
aplay results in a variety of error messages, or -- more recently -- a
terrible stream of screeching and popping.  I've followed the Gentoo
install handbook and ALSA guide.  I've tried alsa compiled into the
kernel (which I gather is the way it's "supposed to be done" with
2.6), I've tried compiling alsa as a module, I've even tried genkernel
(though I now understand that's not good for 2.6 - is that right?).  

I've gotten several results and error messages in the course of my
efforts; most recently playing .wavs with aplay results in a series of
ugly-sounding pops and the error message:

ALSA lib pcm_hw.c:578:(snd_pcm_hw_drain) SNDRV_PCM_IOCTL_DRAIN failed:
Input/output error

Before I try to collect and post more detailed error messages, allow
me to ask:  Are there some bits of magic for getting alsa to work
in Gentoo that I'm probably missing?  Can anyone recommend additional
sources of information?

Also: Would it be easier to get sound working with a 2.4 kernel, and
is it worth the downgrade?

Thanks again,

 --Matt.