Would a video help others diagnose the noise?
Funny you should say this - I actually thought the same and tried to capture the noise last night.
This is from inside the car with the right hand side window open and a wooden wall about two yards away after some miles of driving. So this is the mild version: Noise
Also, you could try the old trick of using a screwdriver as a stethoscope to find exactly where it is coming from. Touch the metal end near the point and put your ear to the handle. Noise is transmitted along the screwdriver to your ear.
I'm using the good old screwdriver trick quite often. But with this noise I don't even want to stick my bare ears into the wheel house longer than a few seconds. When it's loud, it's so loud that it actually causes noticeable temporary hearing damage straight away when you come near it (well, I'm a sound engineer so my ears might be a bit more sensitive).
What I noticed:
The noise was strongest and started straight after starting the engine when it was dry.
A few hours later, it only started after about one minute idling but it had been raining for an hour or so. Also, the noise level is much lower when roads are wet. Over the holidays, I had it after every cold start and it would eventually go away after a few minutes / miles and not come back over a 400 km distance until the next cold start in dry weather.