Question New Huawei P Smart 2019 - screen problem(?)

[queensoft]

P Smart 2019, 3 days old
Updated to Android 9.0.1.142

Problem: in some apps / menus, the screen brightness changes by itself.

All screen / brightness options are set to manual - check second 33.
Smart resolution is turned off.
There are no apps that have permission to chenge brightness
Screenshots here: https://drive.google.com/open?id=1zRxA_q5rLWE2N7EAYu5fg7aLfhDTYk9x
The images gets a bit darker than normal / set value.
For some brightness levels (like very dim or full brightness) problem does not occur.
Second 57 - maximum brightness = no problem
01m:16s, very dim = no problem
But for others, it occurs very often.
Check second 12, 22, 29, 49, 1:13, 1:34 - the screen flickers, the image gets a bit darker.
When I go back to previous menu/screen, image is bright again.

Same problem occurs with Colour mode&temperature set to Normal or Vivid (default setting).
Same problem occurs with Nova launcher or Huawei launcher.
Same problem occurs with with USB computer charger connecter or not.

Warranty or is there a setting ?

View: https://www.youtube.com/watch?v=E4bW8GUc4pQ

 

[queensoft]

I think I found the problem: Developer Options > Animator duration scale
Value 0 - problem occurs
Vale 0.5x or greater - no more problems.
I set to zero all 3 values (Transition animation scale, Window animation scale) for the phone to be more responsive.