diff --git a/flake.nix b/flake.nix
index 3433ffa..879ae3e 100644
--- a/flake.nix
+++ b/flake.nix
@@ -1,7 +1,7 @@
 {
   inputs = {
     # Pin nixpkgs to a specific commit
-    nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
+    nixpkgs.url = "github:xinyangli/nixpkgs/deploy";
     nixpkgs-stable.url = "github:nixos/nixpkgs/nixos-24.05";
 
     home-manager = {
diff --git a/machines/calcite/configuration.nix b/machines/calcite/configuration.nix
index 502498d..458e1db 100644
--- a/machines/calcite/configuration.nix
+++ b/machines/calcite/configuration.nix
@@ -110,8 +110,6 @@
   services.printing.enable = true;
   # services.printing.drivers = [ pkgs.hplip ];
 
-  # Enable sound with pipewire.
-  sound.enable = true;
   hardware.pulseaudio.enable = false;
   security.rtkit.enable = true;
   services.pipewire = {