Shakes or Wobbles problem
2004 Jaguar XJ8 V8 Two Wheel Drive Automatic 42000 miles

I just bought a 04 jaguar, and it gives me a slight vibration on the steering wheel when i hit the accelerator @ 49 mph to 55 mph but once it gets up to 60 mph i feel no vibration from the steering wheel nor the accelerator. I had the tires balanced and aligned. Can someone help me w/ this ? Thanks.