Patch snd_usb_audio and add 1824c PipeWire config

hosts/odyssey/default.nix

@@ -19,6 +19,29 @@ with lib.my;
 
   networking.networkmanager.enable = true;
 
+  environment.etc."pipewire/pipewire.conf.d/surround.conf".text = ''
+    context.modules = [
+      {
+        name = libpipewire-module-loopback
+        args = {
+          node.description = "1824c Surround"
+          capture.props = {
+            node.name = "1824c_Speakers"
+            media.class = "Audio/Sink"
+            audio.position = [ FL FR FC SL SR LFE ]
+          }
+          playback.props = {
+            node.name = "playback.1824c_Speakers"
+            audio.position = [ AUX0 AUX1 AUX2 AUX3 AUX4 AUX5 ]
+            target.object = "alsa_output.usb-PreSonus_Studio_1824c_SC4E21110775-00.multichannel-output"
+            stream.dont-remix = true
+            node.passive = true
+          }
+        }
+      }
+    ]
+  '';
+
   nix.package = pkgs.nixFlakes;
   nix.extraOptions = ''
     experimental-features = nix-command flakes