ok I solved the riddle by installing proper mpv... I did not expect it will install wrong version anyway!
and another problem...
[vapoursynth] Script evaluation failed:
[vapoursynth] Python exception: SVSmoothFps: unable to init GPU-based renderer - code 65536
[vapoursynth]
[vapoursynth] Traceback (most recent call last):
[vapoursynth] File "src/cython/vapoursynth.pyx", line 1810, in vapoursynth.vpy_evaluateScript (src/cython/vapoursynth.c:36455)
[vapoursynth] File "/home/bartek/.local/share/SVP4/scripts/738f1c1e.py", line 53, in <module>
[vapoursynth] smooth = interpolate(clip)
[vapoursynth] File "/home/bartek/.local/share/SVP4/scripts/738f1c1e.py", line 36, in interpolate
[vapoursynth] smooth = core.svp2.SmoothFps(input_m,super["clip"],super["data"],vectors["clip"],vectors["data"],smoothfps_params,src=input_um,fps=src_fps)
[vapoursynth] File "src/cython/vapoursynth.pyx", line 1702, in vapoursynth.Function.__call__ (src/cython/vapoursynth.c:34595)
[vapoursynth] vapoursynth.Error: SVSmoothFps: unable to init GPU-based renderer - code 65536
[vapoursynth]
will it ever end?