2004 Nissan Maxima WOBBLE OR SHAKE

I have 4 new tires on my car and they have all been roadforce balanced twice just to make sure it was not a tire or rim problem. I have an annoying shimmy in wheel at low and high speeds and it seems to come and go at differnt speeds. I the repair shop said tire problem but this is the third set of tires and the same problem there. I looked at the tire on the car up on the lift while it was spinnig it looks like a wobble what can this be.