This is my scenario:

I need to start an activity when screen goes on, no problem, just it works slow(take a second at least).

So what I did is start the activity when screen goes of, and just wait till user turn his screen.

Now my problem is that the activity opens the lock screen, which is what I want, but it makes the unlock sound when screen goes of. Is there a possibility to cancel the sound? Or maybe make the activation when screen on work faster?