Echoing Bryan ^ although I just had a very similar issue except it was not a subtle hum. Had a pebble wedged between the back of my front driver side rotor and the shield....was absolutely deafening. Luckily no serious damage :)
Selling a pair of FK510s I used for the rear for about 3 weeks. Looking to sell them local to the SF Bay Area, not looking to ship.
Only used for daily commute, have not run these on back roads or monkey mode.
Tire spec: 295/30/18 x2
DM if interested, will check comments/replies on this post...
For me, it felt like the o-ring around the hose end where you attach the vent hose to the intake pipe gave me some trouble, probably a lot of friction? I ended up going full ape mode and pulling it off (in a lateral motion)