Hi, I've got a Samsung galaxy s3 and a few things are happening and it's abit worrying. Firstly when I press the power button or the main key on the phone to the unlock screen sometimes my screen flashes purple for a split second then to goes to the unlock screen and ive looked all over the Internet and have found nothing.*Secondly when I receive a call and I have my headphones in and I unplug them to answer when I finish the call music starts playing out of my phone speaker, this has happened when I haven't been playing music through my headphone but they've been plugged in.*Lastly (my brightness is on the lowest setting) sometimes when I press the power or key to go to the lock screen the screen goes really bright (like its on the highest brightness) and it says on settings the brighness is still on the lowest it can be and I have to lock my phone for the brighness to go back to normal, this id alot more common than the purple screen and both never happen at the same time.I don't know what to do about this and any diagnosis or advice on any of these problems would be a great help.Thanks in advance.