diff --git a/iOS/GBBackgroundView.h b/iOS/GBBackgroundView.h
index c36260f..9659588 100644
--- a/iOS/GBBackgroundView.h
+++ b/iOS/GBBackgroundView.h
@@ -11,4 +11,5 @@
 
 - (void)enterPreviewMode:(bool)showLabel;
 - (void)reloadThemeImages;
+- (void)fadeOverlayOut;
 @end
diff --git a/iOS/GBViewController.h b/iOS/GBViewController.h
index 096a6b5..3dd1b85 100644
--- a/iOS/GBViewController.h
+++ b/iOS/GBViewController.h
@@ -7,6 +7,7 @@ typedef enum {
     GBRunModeTurbo,
     GBRunModeRewind,
     GBRunModePaused,
+    GBRunModeUnderclock,
 } GBRunMode;
 
 @interface GBViewController : UIViewController <UIApplicationDelegate,
diff --git a/iOS/GBViewController.m b/iOS/GBViewController.m
index 5100eea..ef4819b 100644
--- a/iOS/GBViewController.m
+++ b/iOS/GBViewController.m
@@ -60,6 +60,8 @@
     __weak GCController *_lastController;
     
     dispatch_queue_t _cameraQueue;
+    
+    bool _runModeFromController;
 }
 
 static void loadBootROM(GB_gameboy_t *gb, GB_boot_rom_t type)
@@ -390,9 +392,14 @@ static void rumbleCallback(GB_gameboy_t *gb, double amp)
                 if (button.isAnalog && [[NSUserDefaults standardUserDefaults] boolForKey:@"GBDynamicSpeed"]) {
                     GB_set_clock_multiplier(&_gb, (button.value - analogThreshold) / (1 - analogThreshold) * 3 + 1);
                 }
+                _runModeFromController = true;
+                [_backgroundView fadeOverlayOut];
             }
             else {
-                [self setRunMode:GBRunModeNormal];
+                if (self.runMode == GBRunModeTurbo && _runModeFromController) {
+                    [self setRunMode:GBRunModeNormal];
+                    _runModeFromController = false;
+                }
             }
             break;
         case GBRewind:
@@ -401,22 +408,30 @@ static void rumbleCallback(GB_gameboy_t *gb, double amp)
                 if (button.isAnalog && [[NSUserDefaults standardUserDefaults] boolForKey:@"GBDynamicSpeed"]) {
                     GB_set_clock_multiplier(&_gb, (button.value - analogThreshold) / (1 - analogThreshold) * 4);
                 }
+                _runModeFromController = true;
+                [_backgroundView fadeOverlayOut];
             }
             else {
-                [self setRunMode:GBRunModeNormal];
+                if (self.runMode == GBRunModeRewind && _runModeFromController) {
+                    [self setRunMode:GBRunModeNormal];
+                    _runModeFromController = false;
+                }
             }
             break;
         case GBUnderclock:
             if (button.value > analogThreshold) {
+                [self setRunMode:GBRunModeUnderclock ignoreDynamicSpeed:!button.isAnalog];
                 if (button.isAnalog && [[NSUserDefaults standardUserDefaults] boolForKey:@"GBDynamicSpeed"]) {
                     GB_set_clock_multiplier(&_gb, 1 - ((button.value - analogThreshold) / (1 - analogThreshold) * 0.75));
                 }
-                else {
-                    GB_set_clock_multiplier(&_gb, 0.5);
-                }
+                _runModeFromController = true;
+                [_backgroundView fadeOverlayOut];
             }
             else {
-                GB_set_clock_multiplier(&_gb, 1.0);
+                if (self.runMode == GBRunModeUnderclock && _runModeFromController) {
+                    [self setRunMode:GBRunModeNormal];
+                    _runModeFromController = false;
+                }
             }
             break;
         default: break;
@@ -1030,6 +1045,10 @@ didReceiveNotificationResponse:(UNNotificationResponse *)response
         [_audioLock signal];
         [_audioLock unlock];
     }
+    dispatch_async(dispatch_get_main_queue(), ^{
+        self.runMode = GBRunModeNormal;
+        [_backgroundView fadeOverlayOut];
+    });
 }
 
 
@@ -1161,16 +1180,19 @@ didReceiveNotificationResponse:(UNNotificationResponse *)response
         [_audioClient stop];
     }
     
-    if (_runMode == GBRunModeNormal || _runMode == GBRunModeTurbo) {
+    if (_runMode == GBRunModeNormal || _runMode == GBRunModeTurbo || _runMode == GBRunModeUnderclock) {
         _rewindOver = false;
     }
     
-    if (_runMode == GBRunModeNormal || !([[NSUserDefaults standardUserDefaults] boolForKey:@"GBDynamicSpeed"] && !ignoreDynamicSpeed)) {
+    if (_runMode == GBRunModeNormal  || _runMode == GBRunModeUnderclock || !([[NSUserDefaults standardUserDefaults] boolForKey:@"GBDynamicSpeed"] && !ignoreDynamicSpeed)) {
         if (_runMode == GBRunModeTurbo) {
             double multiplier = [[NSUserDefaults standardUserDefaults] doubleForKey:@"GBTurboSpeed"];
             GB_set_turbo_mode(&_gb, multiplier == 1, false);
             GB_set_clock_multiplier(&_gb, multiplier);
         }
+        else if (_runMode == GBRunModeUnderclock) {
+            GB_set_clock_multiplier(&_gb, 0.5);
+        }
         else {
             GB_set_turbo_mode(&_gb, false, false);
             GB_set_clock_multiplier(&_gb, 1.0);