(!) + ABS lights, buzzy sound when going 60+mph

2009 base Prius with 127,000 m (204,000 km).

Recently had mechanic change front two winter tires. So two different sets for front and back winter tires, but both at 195/65/15.

A few days after, I notice the (!) and (abs) lights come on when I travel above 60 mph (about 100 km/h), but once I'm back down to low speeds it eventually shuts off. And if I drive around low speed streets, it wont come on.

Also speed dependent: buzzing/grinding sound from the front right dashboard when going around 60 mph (100km/h). I drove 6 hours on highways yesterday, constant low buzzing entire time over that speed. Seems to get buzzier if I slant or turn the steering wheel to the left. The buzz is also a little louder if I hit a pothole or hit lower ground, where the car's weight is applied on the tires. In this case the buzz can be a wierd sound like metal scraping on metal...tough to describe.

Planning to bring it by mechanic Monday.

 

Thank you @ChapmanF, I saw in other threads this could be the reality.

Thank you @Patrick Wong:
38 + 42 BACK.
32 + 32 FRONT (mechanic did this - normally I put the fronts to 40).