DP port not working

[ZhongQFish]

Hi, I follow the instruction and installed the Monterey version successfully. I found the mini DP somehow is not working when I use a DP to HDMI cable to connect an external monitor. The external monitor somehow has no signal input or shows a snow screen (static noise). I wonder how can I fix it?

Note: Please use the Discussions tab if you have any ideas or a question.

Describe the bug
A clear and concise description of what the bug is.

Screenshots
If applicable, add screenshots to help explain your problem.

Device (please complete the following information):

• macOS Version:
• EFI Version:
• EFI type (regular or HeliPort):

Additional context
Add any other context about the problem here.