Same issue here since day 1. 2L FWD with O. E. TOYO 18'' tires on. Debbuging, at 1,000 miles 2 tires replaced. Didn't solve. Asked Mazda to perform road force balance. They don't want to. Front passengers side vibrates more than others. Using normal wheel balance, found out that 85 grams weights needed. Seemed to me too much as tire is new. They checked the rim itself without the tire on it, and the rim is not balanced! It showed 70 grams on the outer side and 10 grams on the other. Does it mean the rim is deformed?
This may explain why forum members felt vibration with different tire brands. Maybe there is a factory defect with the rims, or something at the manufacturing floor that makes this defect. Anyhow, the guy crossed the passengers side front right wheel with the left rear one and balanced it rotating the tire against the rim putting 35 and 10 grams instead of the 85 required before. It seems better now, but not perfect. I can feel the vibration specialy when driving a curve - it behaves like a giro ball. I may buy tomorrow the NVH app as JohnG recommended to try and solve this by myself, and would demand Mazda to take it to road force balance.
Yea. My dealer did regular, then road forced, then regular again with Mazda head office tech.
They decided to put Michelin tires on. Fixed 90% of vibration.
I'm happy for now but it's still not a very smooth ride.