I'm using the csl dd (8nm) and I have the same grainy / rattling feeling in my wheel.
It seems to be connected to the tyre friction setting. It's noticeable from around 25 and upwards.
I use it at around 45, with self aligning at 75.
That give me a good feeling of what the tyres are doing, while also helping the wheel self correct.
I would love if they removed the vibration part of the tyre friction setting, (of that is what's causing the unbearable rattling/graining), and leave the force feedback part the way it is.
It is almost gamebreaking with the constant graining, while absolutely necessary, in my Opinion, to balance the overall force feedback with the tyre friction settings.
Please help us EA!