Hondaone

I purchased a Honda HS928TC in the fall of this year. The first time I used the machine it was surging alot, so I call my local dealer and they picked the machine up and took it for service. There was a piece of plastic touching the govenor, so the blower couldn't even itself out. But now when I use it, it still surges unless I drive it into the snow. If I only take a little bit of snow it will surge. Could someone tell me if this is normal for this particular machine or if there is something wrong with it. P.S. the HS928TC is the Canadian model for the HS928TA. Also, it is really bad on shear pins???