Do you connect your RealSense using USB 2.0 or 3.0? It’s important to connect it using USB 3.0.
Please provide us with 2 screenshots from realsense-viewer tool:
- Info tab
- Stereo Module > Resolution (list of modes)
I used the 3.0 interface before, but it always showed 2.1 after insertion, but this problem has been solved now, thank you