so ive been dealing with this for like two weeks now and its driving me nuts. motor 3 on my 5inch freestyle build starts twitching when i push past maybe 40% throttle, like a stutter, not consistent. doesnt do it at low throttle at all. i swapped props thinking maybe a bent blade was causing some weird harmonic thing but still does it.

the motor is a 2306 2450kv that ive had for about a year, definitely taken some hits but nothing that looked catastrophic. i ran motor test in betaflight and it does the same thing there so im pretty confident its not a filtering issue or pid related. just wondering if anyones seen this specific behavior before ? is this more likely a partially shorted winding in the motor or could the ESC FET be going bad on that channel. running a 4in1 45amp ESC stack if that matters.

that sounds like a dying FET to me honestly. ive had the exact same twitching behavior on a 4in1 and when i desoldered the motor and tested it standalone on a different ESC it ran perfectly fine. the motor test in betaflight going through the ESC signal chain still means it could be the ESC outputting garbage at higher duty cycles. if you have a spare ESC or even a single 30x30 unit laying around just wire it up to motor 3 temporarily and see if the behavior goes away. five minutes of work and itll tell you exactly which component is cooked.

could also be a bad solder joint on the motor phase wire, i had something similar and it was just a cold joint that was making intermittent contact under vibration load. worth checking before you replace anything expensive. look for any joint that looks dull or grainy instead of shiny.