nixos-config/modules/pipewire.nix

{ config, lib, modulesPath, pkgs, ... }:
let
  bluetoothSupport = config.sbruder.full;
in
lib.mkIf config.sbruder.gui.enable {
  sound.enable = true;
  security.rtkit.enable = true;
  services.pipewire = {
    enable = true;

    pulse.enable = true;
    alsa = {
      enable = true;
      support32Bit = true;
    };
  };

  environment.systemPackages = with pkgs; [
    unstable.helvum # patch panel
    pavucontrol
    pulseaudio # pacmd and pactl
  ];

  hardware.bluetooth.enable = lib.mkDefault bluetoothSupport;
  services.blueman.enable = lib.mkDefault bluetoothSupport;

  environment.etc."pipewire/pipewire.conf.d/10-behringer-umc202hd.conf".text = ''
    # This is heavily based on the example from the PipeWire wiki:
    # https://gitlab.freedesktop.org/pipewire/pipewire/-/wikis/Virtual-Devices#behringer-umc404hd-microphoneguitar-virtual-sources
    # It has the problem that the virtual source persists,
    # even when the physical source is disconnected.
    context.modules = [
        {   name = libpipewire-module-loopback
            args = {
                node.description = "UMC202HD Left"
                capture.props = {
                    node.name = "capture.UMC202HD_Left"
                    audio.position = [ FL ]
                    stream.dont-remix = true
                    target.object = "alsa_input.usb-BEHRINGER_UMC202HD_192k_12345678-00.analog-stereo"
                    node.passive = true
                }
                playback.props = {
                    node.name = "UMC202HD_Left"
                    media.class = "Audio/Source"
                    audio.position = [ MONO ]
                }
            }
        }
        {   name = libpipewire-module-loopback
            args = {
                node.description = "UMC202HD Right"
                capture.props = {
                    node.name = "capture.UMC202HD_Right"
                    audio.position = [ FR ]
                    stream.dont-remix = true
                    target.object = "alsa_input.usb-BEHRINGER_UMC202HD_192k_12345678-00.analog-stereo"
                    node.passive = true
                }
                playback.props = {
                    node.name = "UMC202HD_Right"
                    media.class = "Audio/Source"
                    audio.position = [ MONO ]
                }
            }
        }
    ]
  '';
}