High Pitched Noise from Upper Intake Manifold

again, it only does it when it idle as soon as you tap on the gas it goes away right AWAY! it cant be my throttle body because my old engine did[nt do it and wen i got the new engine it still didnt do it until i took off the upper intake to paint it and put it back together. me and my mechanic can't figure out what it is?

please im out of ideas here
Its doesnt seem like its affecting anything alot but i just can;t take the noise anymore i know its there so it bothers me.

im wondering if i should replace all the vacuum hoses going to the intake? if so where do i get the hoses and what size and everything?
 
my intake used to whistle. it was probably due to the ports on the heads being different sizes than the ports on the lower intake. didnt whistle all the time though...just when i got on it sometimes