Help getting started with Roku devices, including setup, connecting your device to your TV, linking a Roku device to your account at my.roku.com/link, adding channels, subscribing to services, and more.
Does the device have a power light on? What Roku model device are you using? How are you powering the device? Is it plugged into the TV USB port or is it plugged into a wall outlet? Have you tried switching out the HDMI cable to see if that resolves the issue?