[mwonter]

Unlikely this will help, as I'm on a PC and use utorrent, but I had trouble with .torrent files I created with utorrent, and switched to making my .torrent files with traderslittlehelper, checking the "Private Torrent" box, and then use the "PID" .torrent file TTD creates when you post a show.

Shot in the dark, could it be an easy caused by an update of transmission? You could try an earlier build that predates your problems.

Hope you get a good answer and solve this problem.