/etc/udev/rules.d/40-alsa.rules

KERNEL=="controlC[0-9]*",       NAME="snd/%k", MODE="0660", GROUP="audio"
KERNEL=="hwC[D0-9]*",           NAME="snd/%k", MODE="0660", GROUP="audio"
KERNEL=="pcmC[D0-9cp]*",        NAME="snd/%k", MODE="0660", GROUP="audio"
KERNEL=="midiC[D0-9]*",         NAME="snd/%k", MODE="0660", GROUP="audio"
KERNEL=="timer",                NAME="snd/%k", MODE="0660", GROUP="audio"
KERNEL=="seq",                  NAME="snd/%k", MODE="0660", GROUP="audio"
KERNEL=="mixer0",               SYMLINK+="mixer", MODE="0660", GROUP="audio"
KERNEL=="dsp0",                 SYMLINK+="dsp", MODE="0660", GROUP="audio"
KERNEL=="dsp",                  MODE="0660", GROUP="audio"
KERNEL=="audio0",               SYMLINK+="audio", MODE="0660", GROUP="audio"