so ive had my mini 4 pro for about 3 months now and most of the time its totally fine but lately i keep noticing it drifts to the left when im just hovering, like even when i let go of the sticks it slowly creeps. i checked the GPS and it shows like 14-16 satellites so thats not the issue i think. i calibrated the compass before flying because i always do that near my house which is kind of near some power lines now that i think about it... could that be it? or is something wrong with the imu? i dont really know the difference between calibrating the compass and the imu or when you're supposed to do each one. this is my first drone so maybe im missing something obvious but it feels like it shouldnt be doing this

the power lines thing is almost definitely your problem, or at least part of it. you should never calibrate the compass near anything that messes with magnetic fields ? power lines, cars, metal structures, even some buildings. find an open field or park away from all that and redo it. the imu calibration is different, thats more about the accelerometers and you do that on a flat stable surface indoors, DJI has a walkthrough in the app under safety settings i think. try the compass recal first somewhere clean and see if that fixes the drift before you go down the imu rabbit hole

had literally the exact same thing with my mini 3, drove me crazy for weeks. turned out i was calibrating in my driveway next to my car the whole time lol. moved to a field and never had the issue again. also worth checking if theres any wind at low altitude because sometimes what feels like drift is actually just wind you cant really feel on the ground