Why is my streaming quality bad?

I'm currently helpless what happened to my stream quality:
I haven't changed any of the settings and still the quality has deteriorated.

I stream on Twitch using Streamlabs OBS

My hardware:
GPU: AMD Radeon xfx 5700xt
CPU: Ryzen 7 3800x OC at 4.5 Ghz
RAM: 16GB G.Skill Aegis 3200 dimm DDR4
Storage: 2x Intenso High Performance SSD 500GB each
Internet: 10 Mbits upload

In the picture I have already reduced my settings, but there are still a lot of frame drops.
I already ran the stream through my CPU and GPU, but both are not so good.
As I said a few weeks ago, things went much better.

If I have forgotten something, please point it out. (Screenshot, information, etc.)

Your internet connection could just be unstable. I hope you are connected via ethernet and not via Wi-Fi?!

My PC is connected via LAN and is running stably.