Is this a separate Roku device, or a tv with Roku built in? What is the Roku model and model number? Does this happen on all inputs?
Without more to go on, this sounds like a television equipment problem to me. For that you need to go to the television manufacturer. Even for Roku TVs, Roku just supplies the operating system, the hardware is the manufacturer's responsibility.
Doug Roku Streaming Stick+ 3810 | TCL Roku TV 43S245/C107X | Roku Streaming Stick 3600
Roku Community Streaming Expert I am not a Roku employee, just a user like you.
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