For openSUSE Tumbleweed run the following as root:
zypper addrepo https://download.opensuse.org/repositories/YaST:Head:Rebuild/openSUSE_Tumbleweed/YaST:Head:Rebuild.repo
zypper refresh
zypper install yast2-sound
For openSUSE Leap 15.2 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/YaST:Head:Rebuild/openSUSE_Leap_15.2/YaST:Head:Rebuild.repo
zypper refresh
zypper install yast2-sound
For openSUSE Factory run the following as root:
zypper addrepo https://download.opensuse.org/repositories/YaST:Head:Rebuild/openSUSE_Factory/YaST:Head:Rebuild.repo
zypper refresh
zypper install yast2-sound