Is the pump "new" it should have come with a "stick-on" piece of high density foam that you place on the bottom of the pump to minimize vibration...
If not you could pick up a piece of HDF and place it between the pump and sump...
You want to use a "closed cell" foam (dense) that wont become a biological waste trap...
Another option...if your "hard piped" (pvc) is to cut the pipe near the pump and join it with a piece of flexible hose which will help to absorb vibration and keep the pump from pushing against the side of the sump.