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We'd like to take a closer look to see if there's anything else we can suggest to help. How are you powering the device? Is it plugged into the TV USB port, or is it plugged into a wall outlet with the provided cables? In addition, have you tried using another HDMI port on your TV as well as trying your device on another TV to see if you are seeing the same issue with no signal?
With more information, we will be able to assist you further.