I have recently noticed a sudden vibration between 25 - 20 mph when I decelerate. It only happens when I travel over 40 mph and brake gently to a stop. The dealer told me (this week) it was the CVT downshifting. It's gotten worse lately. The loaner car they gave me didn't do it.

Anyone experience this or know what it could be?

I experience the exact same thing on my 06 A4 with 8k miles, just started in the last month...haven't yet talked to the dealer about this...I notice that it's worse in cold weather....any possible fix for this problem?

I talked to the service center about the same problem in my B7 2005.5 and they mentioned something regarding the amount of Ethanol that the gas suppliers add to their gas (roughly 10%) and it makes the engine shaking! (in my case some time when it is idle the rpm goes to 600 RPM which is less than the idle RPM of 800 set by Audi)!

Same vibration here on my '06 CVT. I'm taking it in to the dealer next week. It's definitely more pronounced when braking downhill. I'm assuming it's a warped rotor as the same thing happened on my '00 Miata and '91 Corrado.