The other day I was hand winding my 5040, something I usually do about once a month as it is far from a regular wear, and the crown, after about 3 clockwise rotations refused to budge. I could rotate the crown counter clockwise freely, but, I could no longer wind the movement. I checked the back and could see the movement working. Yes, I know, it will have to be serviced and it's been a long time since it's last service. Anyone have an idea what the issue might be... I'm just curious as something like this has never happened on any watch I have ever owned.