HDMI/MHL port can support power supply and HDMI signal simultaneously.

However, some input devices may not be 100% compatible with MHL function but still claim YES.

Please select correct "Power Out" under "MHL Settings" in OSD.

If your devices can't work under HDMI/MHL 2 or HDMI/MHL 3, it's highly possibly not 100% compatible with MHL.

It would be suggested to get power from USB port with an USB cable