Desperate for help with jerking when accelerating (730d)

[miococo]

Sorry for a quite long post, but i am desperate for help, since i cant seem to find the issue.

My car (2009 730d, remapped, 150k miles/250k kms) has an issue when im accelerating from ~1500rpm+ the car starts violently shaking, jerking, and it feels as if the gear slips and catches every second, but the rpm gauge does not jump.
If i keep pressing the pedal this continues, until suddenly the rpm's jump up high and the car continues accelerating normally.

The problem seems also only to occur when the car is warmed up and driven for like 40 minutes. Usually i also get a good 2 accelerations that are normal and after that the issue starts.

Couple times After the shaking and jerking have happened, i have tried to accelerate with D/S mode on, and those accelerations have been normal, allthough i have pressed the accelerator fully during these.

I've also noticed a burning oil like smell, coming from underneath the car (not from engine bay) after driving normally when i have gone home. Havent had the smell after noticing this issue though.

Car drives fine at low speeds.

Im speculating that the problem occurs when the car is using alot of torque, but the acceleration is working fine when starting from a standstill as well, so i dont think the torque would be too much.

For diagnosis i have done:
Changed fuel filter
Checked transmission fluid level and quality.(color is good and does not smell burnt, fluid is only 15k kms old)
Checked for codes (no codes)
Checked injectors with ista (says all ok)
Resetted the transmission adaptations.

Any help is appreciated!