(In reply to ruixinli7-c from comment #0)
> Summary:
> 
> When I clicked the mute button at the main page, the music is successfully
> muted. Nevertheless, when I then clicked the game button, say "IELTS" button
> and then redirect to the playing scene, The music is continuously changed
> between on and off and the button is continuously changed between muted and
> unmuted.
> 
> Steps to reproduce:
> 
> 1. entering the game and in the login scene, click the mute button.
> 2. Click the "IELTS" button to redirect to the playing scene.
> 3. In the playing scene, you will find the problem described above.
> 
> Expected result:
> 
> It is expected after clicking the mute button and before clicking unmute,
> the figure of the button will not change and the music should not play.
> 
> Actual result:
> 
> After clicking the mute button and before clicking unmute, the figure of the
> button continuously changed between on and off and the button is
> continuously changed between muted and unmuted.
> 
> Suspected bug:
> 
> Sorry, I am not familiar with how you code this part.

Hi, Ruixin! Thanks for the reporting. Actually it is a very serious bug which significantly decrease the user experience. The problem is explained below:

In the music controller class, there is following code:

        @Override
	public void update() {

	for(int i=0; i<GlobalConstants.NUM_GAME_MODE; i++) {
		startButtons[i].handleEvent(mouse.mousePos);
		startButtons[i].update();
	}
	handleEvent(mouse);
        timeElapsed += timer.DeltaTime();
	if(timeElapsed >= 300) {
			sequenceIndex++;
			sequenceIndex %= 98;
			timeElapsed -= 300;
		}
		MusicController.getInstance().handleClickEvent(mouse.mousePos);
		mouse.isClicked = false;
	}

Nevertheless, you set mouse.isClicked = false at the end. This will cause trouble when you finish update the music controller. As in the same scene, there are other  class.

I fix this bug by doing the following with some code refactoring:

create:
        private void handleMouseClick(Mouse mouse) {
	    if(mouse.isClicked) {
			 
                MusicController.getInstance().handleClickEvent(mouse.mousePos);

		for(int i=0; i<GlobalConstants.NUM_GAME_MODE; i++) {
			startButtons[i].handleEvent(mouse.mousePos);
			startButtons[i].update();
		}
		mouse.isClicked = false;
	    }
        }
and substitute mouse.clicked by this.