When the Roku powers up, it will send a signal down the HDMI cord. Your TV is configured to look for that and react accordingly. It's doing just that.
Normally, when a Roku goes to sleep, it stays asleep until you wake it up with the remote. That would turn on your TV and change the input to the Roku's HDMI port.
To stop it, I'd suggest one of two things:
- Change the CEC settings on your TV to not awaken and respond to connected devices.
- Get a uninterruptible power supply (UPS) for your TV and Roku. You can find them at Walmart for around $40.
I'm not sure of any other options at this time.
Oh, the remote doesn't figure into the mix for what you're encountering.
Roku Community Streaming Expert
Note: I am not a Roku employee.
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