Drivetrain Aod Transmission Noise When Putting Into Drive

Any idea what might be the source of this noise? It doesn't happen all the time, only some mornings when the car has sat over night. I've attached a video here, but noticed some players will only play the audio. Here is the description for audio only. The clicking is me putting it into either park, drive or reverse. You'll hear the "warble" noise shortly after I've placed it into those gears.

thoughts?

TIA,

Bruno,

http://www.narino.com/images/trans noise.mp4

ripper - thanks for the reply.

It's an original transmission, and my daily driver so around 250k. I need her to hold together for a while longer while I build up the car fund.

I relinked the file, hopefully it plays for you now.

thanks,

Bruno