clicking in reverse

I know of two jettas with manuel trans that have a loud clicking sound in reverse. It not the cv's as I thought at first when I purchased the car. I have had the car for a year now and no change in sound and it backs up ok. Should I be worried about this noise . Will it send the reverse gear out the side of the tranny some day? My worry is if I get a junker trans it will do the same thing?

What year? My old 91 didn't do so.