Fix an issue where control binds would be duplicated and quickly mult…

…iply.

source/funkin/input/Controls.hx

@@ -527,6 +527,14 @@ class Controls extends FlxActionSet
           action.inputs[i].inputID = toAdd;
         }
         hasReplaced = true;
+      } else if (input.device == KEYBOARD && input.inputID == toAdd) {
+        // This key is already bound!
+        if (hasReplaced) {
+          // Remove the duplicate keybind, don't replace.
+          action.inputs.remove(input);
+        } else {
+          hasReplaced = true;
+        }
       }
     }
 
@@ -989,6 +997,7 @@ class Controls extends FlxActionSet
     for (control in Control.createAll())
     {
       var inputs:Array<Int> = Reflect.field(data, control.getName());
+      inputs = inputs.unique();
       if (inputs != null)
       {
         if (inputs.length == 0) {
@@ -1038,7 +1047,11 @@ class Controls extends FlxActionSet
       var inputs = getInputsFor(control, device);
       isEmpty = isEmpty && inputs.length == 0;
 
-      if (inputs.length == 0) inputs = [FlxKey.NONE];
+      if (inputs.length == 0) {
+        inputs = [FlxKey.NONE];
+      } else {
+        inputs = inputs.unique();
+      }
 
       Reflect.setField(data, control.getName(), inputs);
     }