I'm 1100 miles in on my Pirelli 22" P-Zeros M Sport. Dropped the air pressure by 5lbs per tire and have noticed a 20% reduction in the "hollow humming" noise. Yes, on fresh blacktop, the sound drops to 10%, but still there for sure. There is no way this is normal or acceptable. I noticed it on day 2 of owning the car... and notified my salesman, but have been unable to get it reviewed yet due to Covid. Pirelli has foam lined tires I see on their site.
https://www.pirelli.com/tires/en-us/...ncs-technology
Does anyone know if foam can be added to tires?