Lags on broadcasts and recordings?

Question

Video

Good day. I ran into a very strange problem: when recording a video or broadcasting, the FPS sags (the picture twitches), and everything is ok in my game, there are no lags. Tried capturing the screen/window/screen area and all the same. This happens in all games/programs, even in the browser. There is a small note: if you set not 60, but 120 fps on the bandicam recording, the drawdowns almost completely disappear. I searched a lot of forums, but none of the solutions suggested there helped.
For video recording I use bandicam, for broadcasts obs.
Config:
- i5 9400f
- 1660super
- 16gb RAM
- 120 ssd (system and software on it)
- 1TB (games and multimedia on it)
Program settings:



Video at 60 fps
Video at 120 fps