At least not on my default 5.2 installation. And the /etc/rc.d/init.d/sound incorrectly states that it uses /etc/.aumixrc although it is /etc/aumixrc. Once the mixer settings are saved with -S things will be fine. Until then if you take out the > /dev/null from /etc/rc.d/init.d/sound you will see that the mixer settings aren't loaded. So either do once a manual aumix -S or rename /etc/.aumixrc to /etc/aumixrc.
fixed in rhsound-1.8-1. Still, it won't load the mixer settings until they're saved at least once, because there's nothing to load them from...