Why does the picture shake

Deanna Sims  this could be an issue with the input sources. Make sure that your cables are all clean and seated properly. If you are uses a cable box etc. try a reboot. You also want to try all other input sources like coax, composite, HDMI etc. If none of this will make a difference then you are most likely having to remove the back of your TV and check the main board as well as all teh cables going to it. If you can post some video on youtube or other sides so we can see the shaking. It could also be the backlight that does some flickering and is perceived as shaking. We need to se what you see