When I adjust the volume on my HTR-4065 receiver, the video signal blinks. Make sure that your HDMI input sources are all set to output at least 480p.
For cable boxes it would be listed under Videos Settings/SD Override. For more info, contact your cable box provider.
Blu-Ray/DVD players it woudl be listed under Vides Settings/TV Settings/Type. For more info, contact your player's support line.
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