Despite what Adamo has said recently, they've been struggling to find the required improvement from their current R5.
Fingers crossed for them they've made some steps in the last month or 2.
The lack of noise has been an issue since GpN was introduced when they had to change the rules to try to make the cars noisier so that spectators could hear them coming.
If you are home bored, this video featuring edge-of-the-seat stuff is quite a treat: https://www.youtube.com/watch?v=vjvYvDKmKKQ
Video Thread