The Nissan Path

So I have a 2005 Pathfinder SE. Just got it actually. The one drawback that I didn't like about the test drive was a squeaking/creaking sound that seemed to come from the gear shifter knob area. I considered it a minor drawback, something that I could fix down the road. I took the center console and gear shifter apart today but couldn't find the source of the sound. It only happens when in gear with the engine running. When I turn the engine off and rock the vehicle back and forth there is no sound. This Pathfinder also had the transmission replaced back in May so I'm wondering if something is not lined up properly or needs some lubrication. I've googled what it could be several times but I haven't seen any good solutions or sources. I'd like to be able to figure this out myself instead of taking it somewhere but I've kinda hit a wall with it all. Its a beautiful vehicle inside and out and I'd like to have it sound that way too. I'd appreciate any suggestions or help! THanks!

Here is a video:

http://www.youtube.com/watch?v=s7Ba2K3AslM