tuedel@tuedel-o-mat:~$ lsof /dev/dsp* /dev/snd/*
COMMAND    PID   USER   FD   TYPE DEVICE SIZE  NODE NAME
mixer_app 5917 tuedel   18u   CHR  116,7      14630 /dev/snd/controlC0
firefox-b 5946 tuedel  mem    CHR  116,5      14594 /dev/snd/pcmC0D0p
firefox-b 5946 tuedel   78r   CHR  116,2      14323 /dev/snd/timer
firefox-b 5946 tuedel   80u   CHR  116,5      14594 /dev/snd/pcmC0