As with anything 'strange noise in cars' it's a bit hard to describe, but I'll try.
For background, my iD.3, which I had for nearly a year was near silent.
- The noise isn't the VESS.
- It usually occurs above 30mph, and comes and goes, getting gradually louder (although only to a just audible level), and then quieter.
- It does seem to happen more in warmer, drier weather.
- It does sound as if it's related to something rotational.
- I can 'feel' the noise slightly in the pedal when it occurs.
- It sounds like something metal against something metal.
- It does 'seem' to get a little deeper in tone as the car slows, which to me would fit with coming from something rotating.
- It could be the tyre noise, as they are lower profile and bigger than the iD.3, but I thought if it was it might settle down after a couple of thousand miles, but it doesn't appear to have.
- It could be something catching on the brakes, but I've checked them after a drive and the discs and drums are always cool to the touch.