Rolling radius perhaps ? What size tyres are you running i had this issue when i was in the middle of a tyre changeover

I was running 245/40/18 front and 275/35/18 rear

I put 265/35/18 on the rear and had the issues you mentioned above it was only when i changed the fronts to 235/40/18 did it all balance back out again, that few mm makes a difference