Brightness resonance in portrait mode

[CAMOKATBETEPAHA]

ssc338q (infinity6e family), imx415, 16 MB nor flash, 2.4.09.05-lite, openipc-ssc338q

In portrait mode (90 or 270 degrees), the image sometimes starts to change brightness cyclically. As a rule, this happens during the transition from day to night when the shutter is triggered, or with a static image at maximum illumination. If you turn the image to normal mode (0 degrees), the image does not float like that.

Example image, day:

Day-night transition:

Changing any settings in Majestic does not help. Only rotating the image by 0 degrees helps. . Also, the problem is clearly not in the I-frames
The problem occurs on all cameras that have a portrait mode, as well as on two video stream channels 1 and 2: