diff --git a/app/src/main/java/be/ugent/zeus/hydra/urgent/MediaNotificationBuilder.java b/app/src/main/java/be/ugent/zeus/hydra/urgent/MediaNotificationBuilder.java
index ec748ee39..efc71eea4 100644
--- a/app/src/main/java/be/ugent/zeus/hydra/urgent/MediaNotificationBuilder.java
+++ b/app/src/main/java/be/ugent/zeus/hydra/urgent/MediaNotificationBuilder.java
@@ -52,6 +52,10 @@ class MediaNotificationBuilder {
 
     Notification buildNotification(MediaSessionCompat mediaSession) {
         MediaControllerCompat controller = mediaSession.getController();
+        var playbackState = controller.getPlaybackState();
+        if (playbackState == null) {
+            return null; // Nothing we can do currently.
+        }
 
         // Construct the actual notification
         NotificationCompat.Builder builder = new NotificationCompat.Builder(context, ChannelCreator.URGENT_CHANNEL);
@@ -65,10 +69,10 @@ Notification buildNotification(MediaSessionCompat mediaSession) {
                         .setShowActionsInCompactView(0);
 
         // Construct the play/pause button.
-        boolean isPlaying = controller.getPlaybackState().getState() == PlaybackStateCompat.STATE_PLAYING;
-        boolean isConnecting = controller.getPlaybackState().getState() == PlaybackStateCompat.STATE_CONNECTING
-                || controller.getPlaybackState().getState() == PlaybackStateCompat.STATE_BUFFERING;
-        boolean isError = controller.getPlaybackState().getState() == PlaybackStateCompat.STATE_ERROR;
+        boolean isPlaying = playbackState.getState() == PlaybackStateCompat.STATE_PLAYING;
+        boolean isConnecting = playbackState.getState() == PlaybackStateCompat.STATE_CONNECTING
+                || playbackState.getState() == PlaybackStateCompat.STATE_BUFFERING;
+        boolean isError = playbackState.getState() == PlaybackStateCompat.STATE_ERROR;
         if (isPlaying || isConnecting) {
             builder.addAction(new NotificationCompat.Action(
                     R.drawable.noti_ic_stop,
diff --git a/flake.lock b/flake.lock
index 38c5dee1d..4b8943aec 100644
--- a/flake.lock
+++ b/flake.lock
@@ -8,11 +8,11 @@
         "systems": "systems"
       },
       "locked": {
-        "lastModified": 1695973661,
-        "narHash": "sha256-BP2H4c42GThPIhERtTpV1yCtwQHYHEKdRu7pjrmQAwo=",
+        "lastModified": 1701787589,
+        "narHash": "sha256-ce+oQR4Zq9VOsLoh9bZT8Ip9PaMLcjjBUHVPzW5d7Cw=",
         "owner": "numtide",
         "repo": "devshell",
-        "rev": "cd4e2fda3150dd2f689caeac07b7f47df5197c31",
+        "rev": "44ddedcbcfc2d52a76b64fb6122f209881bd3e1e",
         "type": "github"
       },
       "original": {
@@ -26,11 +26,11 @@
         "systems": "systems_2"
       },
       "locked": {
-        "lastModified": 1694529238,
-        "narHash": "sha256-zsNZZGTGnMOf9YpHKJqMSsa0dXbfmxeoJ7xHlrt+xmY=",
+        "lastModified": 1701680307,
+        "narHash": "sha256-kAuep2h5ajznlPMD9rnQyffWG8EM/C73lejGofXvdM8=",
         "owner": "numtide",
         "repo": "flake-utils",
-        "rev": "ff7b65b44d01cf9ba6a71320833626af21126384",
+        "rev": "4022d587cbbfd70fe950c1e2083a02621806a725",
         "type": "github"
       },
       "original": {
@@ -41,11 +41,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1698134075,
-        "narHash": "sha256-foCD+nuKzfh49bIoiCBur4+Fx1nozo+4C/6k8BYk4sg=",
+        "lastModified": 1702151865,
+        "narHash": "sha256-9VAt19t6yQa7pHZLDbil/QctAgVsA66DLnzdRGqDisg=",
         "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "8efd5d1e283604f75a808a20e6cde0ef313d07d4",
+        "rev": "666fc80e7b2afb570462423cb0e1cf1a3a34fedd",
         "type": "github"
       },
       "original": {
diff --git a/flake.nix b/flake.nix
index 8c90800c1..0a85b588e 100644
--- a/flake.nix
+++ b/flake.nix
@@ -25,10 +25,13 @@
             toolsVersion = null;
             platformToolsVersion = androidVersions.platformToolsVersion;
             buildToolsVersions = [ androidVersions.buildToolsVersions ];
-            includeEmulator = false;
+            includeEmulator = true;
+            emulatorVersion = "34.1.9";
+            includeSystemImages = true;
+            systemImageTypes = [ "google_apis_playstore" ];
+            abiVersions = [ "x86_64" ];
             platformVersions = [ androidVersions.platformVersions ];
-            # Enable once nixpkgs is fixed...
-            includeSources = false;
+            includeSources = true;
             includeNDK = false;
             useGoogleAPIs = true;
             includeExtras = [
diff --git a/gradle.properties b/gradle.properties
index b9cd10eba..a5e1a0d32 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -20,7 +20,6 @@
 # SOFTWARE.
 #
 
-android.defaults.buildfeatures.buildconfig=true
 android.nonFinalResIds=false
 android.nonTransitiveRClass=false
 android.useAndroidX=true