Motor shaking?

[etnies86]

Hey guys I noticed today my truck was shaking at the red light, like nothing violent just enough that sitting in the cab you could feel it a little. I turned ths truck off and back on and it went away.. I noticed on some cold mornings it sounded a little "clacky" like a 6.0 would with a bad injector but not so intense I was thinking maybe a bad injector last thing I want is a bad injector to wash out a piston. Any ideas?
Also for the last month its had a bouncing idle somedays at red lights turn it off and back on its fine..
Heres a video of the rpm's bouncing at the red light I changed upper and lower fuel filters air filter everythings good on it.
(sorry for the video being sideways)

[etnies86]

Heres a link I hope works to see the video
DropShots.com

[K1LLsW1TchEd]

Might be an injector acting up. Try putting a fuel additive in the tank see if it clears up.