X11 plus weird sound from motor

No you did not, the batt1 file has not changed :frowning:

And is your MOT_THST_HOVER 0.2 or 0.13? That is not clear and is important for step 19

Did you fly for at least 30 seconds in ALT_HOLD mode in order for the FC to learn the MOT_THST_HOVER value?

Read section 3 again if you are unsure.
Impatience crashes vehicles.