[fritsch]

Frequency requested 733
  min hard:200, soft:200; max soft:756, hard:756
  idle:200, efficient:400, boost:756
Xorg [441]: 0 boosts
kodi.bin [489]: 4 boosts
VideoPlayer [687]: 35 boosts
Kernel (anonymous) boosts: 3840

RPS Autotuning (current "high power" window):
  Avg. up: 42% [above threshold? 90%]
  Avg. down: 0% [below threshold? 70%]

So we see here, that VP boosts the GPU, but it sadly only upclocks when it uses > 90% and downclocks right away when using < 70%.

Try to echo 400 into that file and see if it already helps. If not try with 756. i915_min_freq