If your external monitor is not working through the Dual USB-C Hub for Surface Pro 9 (ST-HSP9P), the usual causes are a hub that is not fully seated on both ports, the wrong input selected on the monitor, or a video adapter in the chain instead of a direct HDMI cable. The Dual USB-C Hub for Surface Pro 9 outputs up to 4K at 60Hz from its HDMI port and up to 6K at 60Hz from its USB4 port.

How to fix display problems with the Dual USB-C Hub for Surface Pro 9

1. Confirm you have a Surface Pro 9. The Dual USB-C Hub for Surface Pro 9 is designed exclusively for that model because the USB-C connector spacing is specific to it. It is not compatible with the Surface Pro 8, the Surface Laptop Studio, MacBooks, or other computers and tablets.
2. Seat the hub into both Thunderbolt ports on your Surface Pro 9 at the same time, with the Satechi logo facing toward the screen.
3. Connect your monitor to the HDMI port using a direct HDMI to HDMI cable. Video adapters and converter cables in the middle are a common reason a display stays blank.
4. Switch your monitor to the HDMI input you actually plugged into.
5. On your Surface Pro 9, open Settings, go to System, then Display, and select Detect.
6. Try a different HDMI cable.
7. Connect the monitor straight to your Surface Pro 9 without the hub to confirm the monitor and cable work.
8. Disconnect the Dual USB-C Hub for Surface Pro 9, wait a few seconds, then reconnect it and check again.
9. If you are running two monitors, connect one to the USB4 port and the other to the HDMI port using a direct HDMI to HDMI connection.
10. Set the right expectation on refresh rate. The Dual USB-C Hub for Surface Pro 9 supports resolutions up to 6K, but the refresh rate is capped at 60Hz even on a high refresh rate monitor.
11. If you are using the USB4 port for video, keep your Surface Pro 9 powered with its own charger unless your monitor supplies charging over USB-C. When a monitor is connected to the USB4 port, the hub outputs video and charges the Surface Pro 9 only if the monitor and cable support Power Delivery (PD).