I have noticed a higher pitched whistling type of noise coming from the engine compartment whenever I press the accelerator pedal. I can be either moving or at still. The noise is most noticeable starting at around 1200 rpm all the way up to 1800 rpm or so when the engine sound drowns it out. I made a video from inside the car in a parking garage. The car is otherwise running well and my mechanic recently checked for any vacuum hose leaks. I have read that the fan clutch can produce sounds that varies with the rpm but am not sure if this is indeed the problem. Can anyone help me point to or diagnose the source of the noise? Thank you for any suggestion or help!