Apparently, due to UDEV, ALSA doesn't always work well with multiple sound cards. It doesn't always keep the same priority order from one boot to the next. So sometimes when I would boot up to KDE, the wrong soundcard would be showing through "alsamixer" (I wasn't hearing sound).
See the info here on the ALSA wiki:
http://alsa.opensrc.org/index.php/MultipleCards#Wrong_sound_cards_orderMy fix for this was adding my own ALSA restart script at startup (rc4). Works like a charm now.
Just thought I'd share.