Just to let you all know. I solved this problem of mine by myself, no thanks to my fysio
I had/have very tight and overly active chest (pecs) and weak upper back. Also my upper trapezius is dominant compared to lower trapezius. I've been stretching and massaging pecs, lats and traps. Also by doing lots of rowing, facepulls and heavy rack pulls have helped my situation. Since I started doing heavy rack pulls and back extensions my clean PR got up over 10kg in just couple of weeks.
Feel stronger than ever. Thanks.