Although bug7366 fixes the incorrect if syntax, to enable loading of the
mixer settings, the process is not displayed in the normal manner.
This is because the line that actually loads the settings says:

action "Loading mixer settings" /bin/aumix-minimal -f /etc/.aumixrc -L
>/dev/null

which causes also the [OK] message, generated by the action function, to go
to /dev/null, which is probably not what was intended. The simplest fix is
to just remove the ">/dev/null" part. You could also try stuff like

action "Loading mixer settings" '/bin/aumix-minimal -f /etc/.aumixrc -L
>/dev/null'

but I'm not sure if this will work correctly.