Don't clear your catsettings, that's not the problem. This is most likely the autosave feature, by default it is set to autosave every 30 minutes. If I recall, the setting is in Tools>Options>General, on the first page.
I suggest you use the incremental backup option instead, I have had very good fortune with that. Or you can switch autosave off entirely, that's up to you and how much you might risk in case of the program crashing or the power going out...
Cheers,
Mark