Ever since 2.77, it started crashing for no apparent reason whatsoever.
Every single time, it has to check everything again, it functions normally for a time, starts downloading and then I'm gonna check what has finished... Crash.
And I don't mean that it crashes when I'm going to open. It has crashed sometime between.

what OS?
are you sending in the crash reports? that's the best way to get this fixed.
do you have a lot of torrents loaded/running?
are you in many channels?