If your robot X9 Pro runs with a loud noise, you can try the general troubleshooting steps for noise issues and let us know what happens: 

1. Pause the ACS station and remove the dustbin, clean the suction inlet, and check to make sure the filters are properly aligned.

2. Remove the brush guard and roller brush, run the vacuum without the 2 parts, and let us know whether the noise persists when running without the parts.

3. Confirm if the roller brush shaft sleeve has been installed.

4. Remove the side brush and check if the noise disappears. 

5. Check if there is any foreign object stuck in the wheels and rotate them by hand to see if there is any noise. 

6. Switch between different suction power levels and check if the noise changes with the suction power level. 

By following these steps, you can identify the source of the noise and take appropriate action to fix the issue.