diff --git a/modules/installer/cd-dvd/channel.nix b/modules/installer/cd-dvd/channel.nix
index bc758e0ad6e5..8126ce46dd92 100644
--- a/modules/installer/cd-dvd/channel.nix
+++ b/modules/installer/cd-dvd/channel.nix
@@ -32,7 +32,8 @@ in
       if ! [ -e /var/lib/nixos/did-channel-init ]; then
         echo "unpacking the NixOS/Nixpkgs sources..."
         mkdir -p /nix/var/nix/profiles/per-user/root
-        ${config.environment.nix}/bin/nix-env -p /nix/var/nix/profiles/per-user/root/channels -i ${channelSources} --quiet
+        ${config.environment.nix}/bin/nix-env -p /nix/var/nix/profiles/per-user/root/channels \
+          -i ${channelSources} --quiet --option use-substitutes false
         mkdir -m 0700 -p /root/.nix-defexpr
         ln -s /nix/var/nix/profiles/per-user/root/channels /root/.nix-defexpr/channels
         mkdir -m 0755 -p /var/lib/nixos