revert from unstable, doesn't run.

nixos/modules/nixos/de/kde.nix

@@ -26,6 +26,18 @@ in
       };
       desktopManager.plasma6.enable = true;
     };
+    # realtime process priority
+    security.rtkit.enable = true;
+
+    # enable pipewire for sound
+    services.pipewire = {
+      enable = true;
+      alsa.enable = true;
+      alsa.support32Bit = true;
+      pulse.enable = true;
+      jack.enable = true;
+    };
+
 
     # extra pkgs and extensions
     environment = {

nixos/profiles/role-workstation.nix

@@ -3,7 +3,7 @@
 # Covers desktops/laptops, expected to have a GUI and do workloads
 # Will have home-manager installs
 let
-  vivaldiOverride = pkgs.unstable.vivaldi.override {
+  vivaldiOverride = pkgs.vivaldi.override {
     proprietaryCodecs = true;
     enableWidevine = true;
   };