Senor cleaning mode on Nex-6 is weak?

Hi.  I own both the original NEX-5 and the new NEX-6, and I have couple lens as well so I change lens from time to time.

When I have dust problem on NEX-5, using the camera's cleaning mode and a blower always take care of the problem.  But on NEX-6, the cleaning mode seems very weak, and I cannot remove the dust just with a blower anymore after using the cleaning mode.

On NEX-5, right after triggering the sensor cleaning mode, there is a tangible vibration on the camera and a sound that is loud enough for me to hear with the camera a few feet away from my ears.  But on NEX-6, I don't feel the camera vibrate, and the only sound that come out from the camear is a very high pitch that is so weak that I can only hear with the camear pressing against my ears.

Is it normal?  Does Sony dial down the strength of NEX's sensor cleaning mode after the original NEX-5?