diff --git a/src/AudioToolbox/SystemSound.cs b/src/AudioToolbox/SystemSound.cs
index d159b61a441b..74521dec0143 100644
--- a/src/AudioToolbox/SystemSound.cs
+++ b/src/AudioToolbox/SystemSound.cs
@@ -52,7 +52,7 @@ public class SystemSound : INativeObject, IDisposable {
 
 		Action completionRoutine;
 		GCHandle gc_handle;
-		static readonly Action<SystemSoundId, IntPtr> SoundCompletionCallback = SoundCompletionShared;
+		static readonly AddSystemSoundCompletionCallback SoundCompletionCallback = SoundCompletionShared;
 
 		internal SystemSound (uint soundId, bool ownsHandle)
 		{
@@ -180,9 +180,11 @@ public void PlaySystemSound ()
 			AudioServicesPlaySystemSound (soundId);
 		}
 
-		static unsafe readonly Action<IntPtr> static_action = TrampolineAction;
+		delegate void TrampolineCallback (IntPtr blockPtr);
 
-		[MonoPInvokeCallback (typeof (Action<IntPtr>))]
+		static unsafe readonly TrampolineCallback static_action = TrampolineAction;
+
+		[MonoPInvokeCallback (typeof (TrampolineCallback))]
 		static unsafe void TrampolineAction (IntPtr blockPtr)
 		{
 			var block = (BlockLiteral *) blockPtr;
@@ -295,8 +297,10 @@ public static SystemSound FromFile (string filename)
 			}
 		}
 
+		delegate void AddSystemSoundCompletionCallback (SystemSoundId id, IntPtr clientData);
+
 		[DllImport (Constants.AudioToolboxLibrary)]
-		static extern AudioServicesError AudioServicesAddSystemSoundCompletion (uint soundId, IntPtr runLoop, IntPtr runLoopMode, Action<SystemSoundId, IntPtr> completionRoutine, IntPtr clientData);
+		static extern AudioServicesError AudioServicesAddSystemSoundCompletion (uint soundId, IntPtr runLoop, IntPtr runLoopMode, AddSystemSoundCompletionCallback completionRoutine, IntPtr clientData);
 
 		[MonoPInvokeCallback (typeof (Action<SystemSoundId, IntPtr>))]
 		static void SoundCompletionShared (SystemSoundId id, IntPtr clientData)
diff --git a/tests/monotouch-test/AudioToolbox/SystemSoundTest.cs b/tests/monotouch-test/AudioToolbox/SystemSoundTest.cs
index e0c9e8d7fc71..a362ab89c7e3 100644
--- a/tests/monotouch-test/AudioToolbox/SystemSoundTest.cs
+++ b/tests/monotouch-test/AudioToolbox/SystemSoundTest.cs
@@ -24,7 +24,6 @@ namespace MonoTouchFixtures.AudioToolbox {
 	[Preserve (AllMembers = true)]
 	public class SystemSoundTest
 	{
-#if !MONOMAC // Currently no AppDelegate in xammac_test
 		[Test]
 		public void FromFile ()
 		{
@@ -43,10 +42,9 @@ public void FromFile ()
 					}));
 
 				ss.PlaySystemSound ();
-				Assert.IsTrue (MonoTouchFixtures.AppDelegate.RunAsync (DateTime.Now.AddSeconds (timeout), async () => { }, () => completed), "PlaySystemSound");
+				Assert.IsTrue (TestRuntime.RunAsync (DateTime.Now.AddSeconds (timeout), async () => { }, () => completed), "PlaySystemSound");
 			}
 		}
-#endif
 
 		[Test]
 		public void Properties ()
@@ -59,7 +57,6 @@ public void Properties ()
 			}
 		}
 
-#if !MONOMAC // Currently no AppDelegate in xammac_test
 		[Test]
 		public void TestCallbackPlaySystem ()
 		{
@@ -73,7 +70,7 @@ public void TestCallbackPlaySystem ()
 				const int timeout = 10;
 
 				completed = false;
-				Assert.IsTrue (MonoTouchFixtures.AppDelegate.RunAsync (DateTime.Now.AddSeconds (timeout), async () =>
+				Assert.IsTrue (TestRuntime.RunAsync (DateTime.Now.AddSeconds (timeout), async () =>
 					ss.PlaySystemSound (() => {	completed = true; }
 				), () => completed), "TestCallbackPlaySystem");
 			}
@@ -92,12 +89,11 @@ public void TestCallbackPlayAlert ()
 				const int timeout = 10;
 
 				completed = false;
-				Assert.IsTrue (MonoTouchFixtures.AppDelegate.RunAsync (DateTime.Now.AddSeconds (timeout), async () =>
+				Assert.IsTrue (TestRuntime.RunAsync (DateTime.Now.AddSeconds (timeout), async () =>
 					ss.PlayAlertSound (() => { completed = true; }
 				), () => completed), "TestCallbackPlayAlert");
 			}
 		}
-#endif
 
 		[Test]
 		public void DisposeTest ()