Loud hum in the interior after tyre change

Hello everyone, I put my summer tires back on the car yesterday (Godyear F1, 225/45/r17 from 2006). I had no problems with them until the demonthly last year, now I have changed for reasons of even wear from the rear to the front. Right on the first ride this hum occurred: between 30 and about 60 kmh extremely strong in the interior, but no vibrating of the steering wheel, especially to feel when the car rolls and is not accelerated. I had read a lot about the sawtooth here, I checked the tires, but there was nothing noticeable to discover. So today I switched back (back to the front again), just like the tires were driven last season. The loud hum is still there in the above area, but at least not so extremely loud (you could hardly talk in the car before). I checked tire pressure, and also tried with more now less pressure, without success g. My next step would be to let the tires balance and to have them checked on high stroke, but then I wouldn’t have to have vibrations on the steering wheel? The tires still have between 3.5 and 4.5 mm profile and actually wanted to drive them this summer. Still ideas what I could try ? Greetings and thanks for your input. Joschi