Speedmaster 3861 chrono dial hour skip between 8 and 9

Hi all, wondering if anyone can help me with hour the chronograph works in a 3861. I've recently purchased this watch as my first luxury watch and currently like to have the large minute hand sweeping. It's made in 2023. I've noticed that when i start the chronograph at 12:00 mid day, the hour dial moves correctly until it gets to 8 - 9 where it slows down, see picture attached. The minute sub dial works correctly though.

I'm wondering maybe if the teeth are worn, so when it reaches this time, they do not grip and can not turn the hour dial correctly.

thanks in advance.

Personally never have ran the chrono for extended periods of time on the daily, but wondering if this is happening off a full wind? As you're running the chrono it's eating into the power reserve and if the power reserve was lower to begin with, might be causing this issue. Or it could be something else. Just curious, what troubleshooting have you done to rule things out?