diff --git a/res/controllers/Roland_DJ-505-scripts.js b/res/controllers/Roland_DJ-505-scripts.js
index 476552f8d01..c1ed44d10e9 100644
--- a/res/controllers/Roland_DJ-505-scripts.js
+++ b/res/controllers/Roland_DJ-505-scripts.js
@@ -599,8 +599,12 @@ DJ505.Deck = function(deckNumbers, offset) {
     this.sync = new components.Button({
         midi: [0x90 + offset, 0x02],
         group: "[Channel" + deckNumbers + "]",
-        outKey: "sync_enabled",
+        outKey: "sync_mode",
+        flickerState: false,
         output: function(value, _group, _control) {
+            if (value === 3) {
+                value = this.flickerState;
+            }
             midi.sendShortMsg(this.midi[0], value ? 0x02 : 0x03, this.on);
         },
         input: function(channel, control, value, _status, _group) {
@@ -621,7 +625,15 @@ DJ505.Deck = function(deckNumbers, offset) {
                 script.triggerControl(this.group, "beatsync", 1);
             };
             this.onLongPress = function() {
-                engine.setValue(this.group, "sync_enabled", 1);
+                if (engine.getValue(this.group, "sync_enabled")) {
+                    // If already explicit leader, reset explicit state
+                    // (setting it to 0 may still make it implicit leader and
+                    // immediately resetting it to 1).
+                    var value = (engine.getValue(this.group, "sync_master") === 2) ? 0 : 2;
+                    engine.setValue(this.group, "sync_master", value);
+                } else {
+                    engine.setValue(this.group, "sync_enabled", 1);
+                }
             };
         },
         shift: function() {
@@ -632,6 +644,20 @@ DJ505.Deck = function(deckNumbers, offset) {
                 script.toggleControl(this.group, "quantize");
             };
         },
+        connect: function() {
+            components.Button.prototype.connect.call(this); // call parent connect
+            this.flickerTimer = engine.beginTimer(500, function() {
+                this.flickerState = !this.flickerState;
+                this.trigger();
+            }.bind(this));
+        },
+        disconnect: function() {
+            components.Button.prototype.disconnect.call(this); // call parent disconnect
+            if (this.flickerTimer) {
+                engine.stopTimer(this.flickerTimer);
+                this.flickerTimer = 0;
+            }
+        },
     });
 
     // =============================== MIXER ====================================