[arch-general] Panic - no sound devices after upgrade

After a routine upgrade it seems I don't have any sound devices any more. More in detail: * The driver for my card (RME HDSP MADI, snd_hdpsm) is loaded. * aplay -L tells me there is only the 'null' device. * (re)starting /etc/rc.d/alsa doesn't change things. * There is *no* /dev/pcm at all. * /sys/class/sound only has a link to a timer device. * No traces in dmesg or /var/log/messages of anything going wrong. I suspect udev fails to do the right things. * /etc/udev/rules.d is empty * /etc/udev/udev.conf contains only the line udev_log="err" This is a professional studio and I'm expecting clients tomorrow at 09:00. Any ideas ? TIA, -- FA