I recently did a complete wipe of my main mythtv system. Since then every few weeks the program data will be completely gone. Every show says "Unknown" To fix it I go to backend setup and without changing anything tell schedules direct to retrieve lineups again after closing the myth fill database runs and all is well. Anything I should check out on why this is happening? Mythbuntu 9.1 with mythtv .22 nvidia drivers, PVR-150 doing the tuning. This is sole backend and frontend on the network.