I just installed Funtoo, and I have no sound. My soundcard is detected and shows up in the multimedia section of system settings but... no sound. Everything is unmuted in kmix, and I am using the VLC phonon backend. Can anyone advise? I have been using KDE 4.x on this box for five or six years and never had a problem with sound before.

To be honest I don't even know what Funtoo is...
could you please be a tad more detailed about your setup: exact KDE release version, do you use Pulseaudio (recommended), did you check alsamixer that nothing is muted? Also which exact application did you use to test if there is sound? The Phonon backend is secondary for now, if the general sound doesn't work alsamixer the first thing to check

Funtoo is a fork of Gentoo that mostly uses Gentoo repos. KDE is 4.14.3. I don't use Pulseaudio but will install it if that will help (although I have no idea how to set it up). I've run the alsamixer and nothing is muted. My user is a member of the audio group. I've tested sound with Clementine, VLC, and Flashplayer.

I've installed pulseaudio and am trying to figure out how to configure it. It added a pulseaudio server device in system settings -> multimedia, reduced the number of channels in kmix... and I still have no sound. All the levels are up and unmuted when I run alsamixer btw.

Fixed. Entered following in /etc/pulse/default.pa:

load-module module-alsa-sink device=hw:0,0
load-module module-alsa-source device=hw:1,0