On my Dangbei projector, I switched the language by going to the Settings menu. Then, I navigated to the System or General section (depending on the model) and found the Language option. From there, I could select English. Hopefully, it's similar to the X5 Ultra!
Maybe contacting Dangbei customer support would be the easiest solution. They can definitely guide you through the process of switching the language to English on your X5 Ultra projector.
