As you see spirit does its job, TC is going down on target rpm, but rpm is still rising. I think this is a ESC issue, if ESC is doing spool-up.
In the manual it says, once rpm are up and steady, fast TC control is used, till this moment, ESC is also influencing rpm out on it's own.
Question is when is this moment, playing with spool up might help.
For me, this is a more cosmetic issue. I used to pitch and Hover or climb out once I have got enough head spin adding some load, so I don't even notice this.
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