V70 D5 215 PS chirps during acceleration under load

Hello, my V70 chirps on the first approx. 15 km while accelerating. There is nothing to hear when giving gas in the stand, I accelerate out of the speed cellar with a little emphasis (no full throttle, engine is not yet warm), a chirping is clearly perceptible. If it were to occur in the stand, I would tap strongly on V-belts, also sounds like that. Since it only occurs under load, I rather tap on the turbo charge. It is definitely not a normal loader whistle, I know that very well, driving exclusively turbo engines for 10 years. Did someone have the noise and know what it is about? Have a nice evening.