diff --git a/osu-framework b/osu-framework
index 87d68cda00..cc013fc406 160000
--- a/osu-framework
+++ b/osu-framework
@@ -1 +1 @@
-Subproject commit 87d68cda0015d51dc3da56d2322fa10d399fc4ed
+Subproject commit cc013fc4063dda0843f38c1c73568a413abcf229
diff --git a/osu.Game/Beatmaps/WorkingBeatmap.cs b/osu.Game/Beatmaps/WorkingBeatmap.cs
index 2a8178882e..8c96074352 100644
--- a/osu.Game/Beatmaps/WorkingBeatmap.cs
+++ b/osu.Game/Beatmaps/WorkingBeatmap.cs
@@ -31,7 +31,7 @@ namespace osu.Game.Beatmaps
             Mods.ValueChanged += mods => applyRateAdjustments();
 
             beatmap = new AsyncLazy<Beatmap>(populateBeatmap);
-            background = new AsyncLazy<Texture>(populateBackground);
+            background = new AsyncLazy<Texture>(populateBackground, b => b == null || !b.IsDisposed);
             track = new AsyncLazy<Track>(populateTrack);
             waveform = new AsyncLazy<Waveform>(populateWaveform);
         }
@@ -99,10 +99,11 @@ namespace osu.Game.Beatmaps
             if (WaveformLoaded) Waveform?.Dispose();
         }
 
-        public void DisposeTrack()
-        {
-            if (TrackLoaded) Track?.Dispose();
-        }
+        /// <summary>
+        /// Eagerly dispose of the audio track associated with this <see cref="WorkingBeatmap"/> (if any).
+        /// Accessing track again will load a fresh instance.
+        /// </summary>
+        public void RecycleTrack() => track.Recycle();
 
         private void applyRateAdjustments(Track t = null)
         {
@@ -114,11 +115,60 @@ namespace osu.Game.Beatmaps
                 mod.ApplyToClock(t);
         }
 
-        public class AsyncLazy<T> : Lazy<Task<T>>
+        public class AsyncLazy<T>
         {
-            public AsyncLazy(Func<T> valueFactory)
-                : base(() => Task.Run(valueFactory))
+            private Lazy<Task<T>> lazy;
+            private readonly Func<T> valueFactory;
+            private readonly Func<T, bool> stillValidFunction;
+
+            private readonly object initLock = new object();
+
+            public AsyncLazy(Func<T> valueFactory, Func<T, bool> stillValidFunction = null)
             {
+                this.valueFactory = valueFactory;
+                this.stillValidFunction = stillValidFunction;
+
+                init();
+            }
+
+            public void Recycle()
+            {
+                if (!IsValueCreated) return;
+
+                (lazy.Value.Result as IDisposable)?.Dispose();
+                init();
+            }
+
+            public bool IsValueCreated
+            {
+                get
+                {
+                    ensureValid();
+                    return lazy.IsValueCreated;
+                }
+            }
+
+            public Task<T> Value
+            {
+                get
+                {
+                    ensureValid();
+                    return lazy.Value;
+                }
+            }
+
+            private void ensureValid()
+            {
+                lock (initLock)
+                {
+                    if (!lazy.IsValueCreated || (stillValidFunction?.Invoke(lazy.Value.Result) ?? true)) return;
+                    init();
+                }
+            }
+
+            private void init()
+            {
+                lazy = new Lazy<Task<T>>(() => Task.Run(valueFactory));
             }
         }
     }
diff --git a/osu.Game/OsuGameBase.cs b/osu.Game/OsuGameBase.cs
index 8eaa20f781..0ddff5e5aa 100644
--- a/osu.Game/OsuGameBase.cs
+++ b/osu.Game/OsuGameBase.cs
@@ -154,7 +154,7 @@ namespace osu.Game
                         Debug.Assert(lastBeatmap != null);
                         Debug.Assert(lastBeatmap.Track != null);
 
-                        lastBeatmap.DisposeTrack();
+                        lastBeatmap.RecycleTrack();
                     }
 
                     Audio.Track.AddItem(b.Track);
diff --git a/osu.Game/Screens/Select/BeatmapCarousel.cs b/osu.Game/Screens/Select/BeatmapCarousel.cs
index b0a636dfb3..3f42ae11ac 100644
--- a/osu.Game/Screens/Select/BeatmapCarousel.cs
+++ b/osu.Game/Screens/Select/BeatmapCarousel.cs
@@ -45,7 +45,7 @@ namespace osu.Game.Screens.Select
 
                 Task.Run(() =>
                 {
-                    newGroups = value.Select(createGroup).ToList();
+                    newGroups = value.Select(createGroup).Where(g => g != null).ToList();
                     criteria.Filter(newGroups);
                 }).ContinueWith(t =>
                 {
@@ -124,16 +124,19 @@ namespace osu.Game.Screens.Select
             // todo: this method should be smarter as to not recreate panels that haven't changed, etc.
             var group = groups.Find(b => b.BeatmapSet.ID == set.ID);
 
-            if (group == null)
-                return;
-
             int i = groups.IndexOf(group);
-            groups.RemoveAt(i);
+            if (i >= 0)
+                groups.RemoveAt(i);
 
             var newGroup = createGroup(set);
 
             if (newGroup != null)
-                groups.Insert(i, newGroup);
+            {
+                if (i >= 0)
+                    groups.Insert(i, newGroup);
+                else
+                    groups.Add(newGroup);
+            }
 
             bool hadSelection = selectedGroup == group;
 
diff --git a/osu.Game/Screens/Select/SongSelect.cs b/osu.Game/Screens/Select/SongSelect.cs
index 6fcaff7976..46284226d7 100644
--- a/osu.Game/Screens/Select/SongSelect.cs
+++ b/osu.Game/Screens/Select/SongSelect.cs
@@ -263,10 +263,7 @@ namespace osu.Game.Screens.Select
             beatmapNoDebounce = beatmap;
 
             if (beatmap == null)
-            {
-                if (!Beatmap.IsDefault)
-                    performLoad();
-            }
+                performLoad();
             else
             {
                 if (beatmap.BeatmapSetInfoID == beatmapNoDebounce?.BeatmapSetInfoID)
diff --git a/osu.Game/osu.Game.csproj b/osu.Game/osu.Game.csproj
index f814cbb3d3..8b6bdefc6c 100644
--- a/osu.Game/osu.Game.csproj
+++ b/osu.Game/osu.Game.csproj
@@ -280,7 +280,7 @@
       <DependentUpon>20171025071459_AddMissingIndexRules.cs</DependentUpon>
     </Compile>
     <Compile Include="Migrations\20171119065731_AddBeatmapOnlineIDUniqueConstraint.cs" />
-    <Compile Include="Migrations\20171119065731_AddBeatmapOnlineIDUniqueConstraint.designer.cs">
+    <Compile Include="Migrations\20171119065731_AddBeatmapOnlineIDUniqueConstraint.Designer.cs">
       <DependentUpon>20171119065731_AddBeatmapOnlineIDUniqueConstraint.cs</DependentUpon>
     </Compile>
     <Compile Include="Migrations\OsuDbContextModelSnapshot.cs" />