Nikon D90 bracketing?

So I'm trying to do HDR with Nikon D90. Using braketing function. -1, neutral & +1 exposure comp. I set the camera on tripod, using IR remote to release. I notice the first shot always move a little bit. 2nd and 3rd align perfectly. It seems like the camera moved between 1st and 2nd shots. First I thought Vibration lense causing this so I have VR turned off. But the problem always there.

Anyone else having this issue with Nikon D90?

Have you tried to use the self-timer to fire the shots?

If you are using an full size tripod you may be encountering shutter release shake due to the tripod being unstable fully extended. Try the tripod at its lowest possession and see if the results are the same. Also try weighing the tripod down.