It depends. It could be the machine heads, it could be an improperly adjusted tremolo system. Another thing it could be is that the strings are expanding as the guitar is played. One of these probably
The best answer for this is: Get a tune-up.
Sometimes. It depends on what is causing the knocking.
Ozzy Osbourne Stop cheating - its for charity !!
if it had a recent tune up then do an oil change. if not clean your air filter. it needs a tune up..
Could be time for a tune up.
the message
Time for a tune up.
bad idle, bad timing, needs tune up , etc.
Time for a tune up.
yess... just listen to "find your love", and you will be able to hear it easily
If you dance to a different tune, you are behaving differently from the others, going your own way, doing your own thing.
If you tune someone, its kind of like you dont have a crush on them but your flirting with them just for the fun of it... and its not going to go anywhere. :) hope that helped