Disc tray constantly opening and closing at random times

Kind of sounds like the power light is acting as if the disc tray is trying to open/close. Have you tried opening and closing the tray a few times to see if the blinking subsides?

If your constantly getting a disc tray open notice when your disc tray is closed, either the disc tray sensor is faulty or the disc tray itself has come off track. You can try to gently wiggle it while it open and if it feels really loose, then its probably
off track. Youll want to contact xbox tech support about getting it fixed or replaced. If youve had your xbox for more than a year, your no longer under warranty and will have to pay for it to be serviced.

It wont read discs at all? Here is a trick you might not have heard yet. Open and close the disc tray but not all the way. Open it and close it like 20 times. Then tell me if your disc is unreadable

Here is what has been working for me... Power on and log in to live. When it says unrecognized disk just keep opening and closing the tray. After 10 times or so it will say open tray or play cd. Then open the tray and go to my games and click blackops 2.
it will say insert disc. manually close the tray and let it read. If it fails try again. I have done this every day since release. (i did install to harddrive. it errored the first time then copied the second time)

I am also having this problem. Its a brand new black 250gb Xbox 360. The disc tray is constantly opening and closing making it impossible to play any games. I don't have a kinect and I tried cleaning the button, to no effect.