Weird sound from the engine bay

Is the radiator fan on? What was the outside temp?

 

Any more details? Was the car ON or READY? Dose the noise continue indefinitely?

 

Sounds like the air conditioner compressor to me. To verify, turn off the AC switch and see if the noise goes away.

If the AC is providing cool air, then no worries.

 

was there pink in your inverter coolant tank?... i've heard a similar sound when air was caught in the lines/pump.

i was going to recommend coolant pump (ice.. non inverter) but that tends to make a chirping noise (from my experiance... unless it's WAY past dying then it could make that noise)

take a tube about 3 or 4 feet long and listen to different spots in your engine bay. (like a child "telephone")

the only other thing i could think of would be a bearing somewhere.... (one of the two or three attached to your "fan belt" (water pump really...)

 

It's really hard to tell just by the recording. Was the noise changing during the recording or it's just that the recorded noise changes because the camera was moved around?

Here is a recording of my AC compressor and other noises:

I would do what Patrick and V8Cobrakid suggested: determine where the sound comes from by either turning things on and off or trying to locate the source of the sound.