Tire noise

I just had my tires rotated and the back tires were put on the front and visa-versa. Now I am noticing rotational noise that seems to be coming from the front tires. I see no obvious deformities of the tires and the tread is good. What is causing it. Thanks for any answers.

You have front wheel drive and you have to wear the rough edges off those front tires (formerly rear)to make the noise stop. The rear wheels will get feathered edges. On a good car, the non driven rear wheels are the ones that get the funny wear.

now, if the tires were taken off the wheels and put on different wheels, they might not have properly balanced one

Thats the sound of tires taking a new “set”, that is getting used to a new wear pattern from being moved to a new location. Because the tires are not running flat across the tread right now, they will have accelerated tread wear until they take a new set and start running flat across the tread again. Then the noise will go away and the tread wear will slow down.

Now if they switched the direction of rotation of the tires by switching sides as well as front to back, then you could have a separated belt in one or more of the tires.