It's interesting that you said that. About a month ago, I emailed someone at the Captioning center and she forwarded my email to someone at Nick, and a few days later, the captioning corrected itself.
I haven't had a problem since.
Here's the email address to Mary Pressman at the Captioning Institute. Please tell her to forward the email to Chris Heaton at Nickelodeon, and he will take care of it. I don't have Chris's email address.
MPresswood@ncicap.org
The other channels are fine, so it has to do something with Nickelodeon.
Good luck!