I installed the freshly new red hat 6.1 on my computer. Everything seemed to work fine except the sound system; under KDE as well under GNOME. The reason found is that the sound subsystem expect to find sound preferences in /etc/sysconfig/sound, and the sndconfig utility produces the /etc/sysconfig/soundcard file. The workaround I used was to symlink soundcard to sound; however, it should be corrected.
This is fixed in the latest KDE packages in Raw Hide. (ftp://ftp.redhat.com/pub/rawhide/)