i am recently getting really annoyed by this noise

im pretty sure its coming from the engine and i dont know what is wrong with it.

it local street since im not going over 50+ i do not hear this noise
however when im on a freeway going 70+ it makes like chick chick chick noise something like loose screw or metal to metal contact.... not sure how to describe the sound.

the noise gets faster and more rapid as the speed(mph) goes up.

one of my friend said it might be the valves and it might need to be adjusted but does anyone have idea what this problem might be?

any thoughts will help... Thank You~ also it will be great to tell me how to fix it.