2005 Honda Accord Throttle Body Noise

My car has developed a very pronounced "humming" type noise that I traced to the throttle body utilizing a stethescope;the noise is always present.Also there is a high pitched "wind" type noise that occurs when the car shifts from 2nd to 3rd gears @ 2000-2500rpm.Techs have ruled out bad alternator as someone suggested...possibly a tranny issue referred to as "harmonic distortion...all baffled...I've already incurred over $500. in dealer repairs to no avail.They replaced belt tensioner;serpentine belt and an exhaust gasket telling me those were the items that were causing the problems...WRONG! Any ideas?My checking account and patience is about tapped out!