It's really tough to put all the blame on one thing, they received some terrible officiating on their west coast trip, but that can never be an excuse. Sadly, it almost appears like a lack of intensity and interest. Other teams are getting up for them like never before and as of late they haven't matched that enthusiasm. The C's are also missing any impact from their bench, overall the bench this year has been an incredible failure, they should be actively pursuing help in this area, if they don't, I don't know if they could repeat as champs.
If they tried to match that level of enthusiasm every single game I think the team will be burned out by the playoffs. I think this is a good reason you do not see teams win back to back championships too often.