Audi question

Not a real nasty one, but it was a pretty deep clunk when going into reverse and drive…didnt do it going into low gears, I just dont get how after I turned the key off and back on it was fine, been driving it all day today and havent had a problem shifting…but i havent gave her a good romp from a dig like i did yesterday.

EDIT: Kind of felt like it was coming from somewhere near the middle back of the car…not so much the front.