Something odd happened last night when I was playing. Something similar happened several months ago. I was playing someone [Fake] Player 4, and the game had just started, with them serving. They never made it past the first serve, because after every serve, and even during each serve, the desychronization error would come up, and the first serve would begin again. We tried a rematch, and this was working better, but in the second game, this started again. Then, on one point, somehow the player went into the menus DURING a point, which I thought was impossible. I retired, and when I tried to rehost, I couldn't.
After some examination, I found that all, or most all, of my settings, such as override IP address, port, all of my player's skill levels, display settings (such as in <profile>.ini, [Display]:Player1=0,Player2=0,Player3=0,Player4=0), and other settings had been set at "0." I had a backup of my profiles, so I was able to restore my profile. I really think that the person that I was playing with did this to me, although I know that may sound paranoid. When I play with someone, is there some way that they could have the ability to change these settings, maybe through some type of access that the game has in order for administrative things to take place (access which normally only you or programmed game functions would have)?
I can post more of my files if you need them.