I had a drop, too (for me it's a different amount, 16k, because my arena is smaller than your and I've just (re)started play). I was on 2L games streak and I had TV game, too.
I don't think TV game changed something. Like JoeMaverick says, I think it could be the losses streak and the opponent (I was against 4th seed in the other conference and I'm 3th seed in mine).
I think that could be even a post-ASG effect, but I'm not sure about that. I remember (in my first experience here) that, in the seasons following a promotion, after ASG break, the fans enthusiasm drop and you could have situation like this. This is not my case because is the first complete season I'm playing (I've started in the last third of the past season and I lost in the playout always in IV division). I saw even you didn't have promotion last year, so probably this won't count