Might the file /etc/asound.conf an issue?
With my previous OS (CentOS 5.6) this file looked like:
#Generated by system-config-soundcard, do not edit by hand
though in Fedora 17, this file is blank except for the comments:
# Place your global alsa-lib configuration here...
Also, in the past, with CentOS and other RedHat distributions,
I use to use the tool system-config-soundcard. It does
not appear that this tool is still available for Fedora17.
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