01 passat engine mounts

I have an issue when I step on it going up a hill or actually backing out of a driveway. Sounds like a wheezing rattle. A local mech thinks it is the engine mounts. Problem is, when I switch from the automatic to the triptronic shifter the noise goes away. Has anyone run into this. FYI - its the 1.8t, 2001 with the sludge issues. VW replaced the engine about a year ago. Thanks for any help.