Sometimes just a simple mixer change will cause a problem.
Are you certain following that “openSUSE Tweak : Increase openSUSE Speed & Performance” guide caused your problem? If it did, you will likely have to reverse everything, until you find what caused the problem. Presumably you recorded your settings BEFORE you changed everything?
You could show us your mixer settings, by typing with root permissions in a gnome terminal or a kde konsole:
/usr/sbin/alsa-info.sh
Type that twice. The first time to update the script, and the second time to have it provide you a URL where your mixer (and other configuration) settings will be posted. Then post that URL here. Post just the URL … nothing else.