Is Top Thrill Dragster Dying?

Earlier this year I saw a video of TTD where there was a double roll back. From what I heard, this had never happened before and I thought it might be a fluke. Well, yesterday at CP I witnessed multiple roll backs on TTD over the course of the day and there was a few times where it looked like it might stall at the top.

Now, yesterday was a ideal day for weather. Upper 70's, no clouds, no wind. What I am wondering is if the engine for TTD might be dying and is not able to reach the required force to push the measured weight of the coaster up the hill. Just a thought, does anyone have any other info on this?