Please check another set in the home if available and see if this issue exist on that set as well. If this is the only set in the home, please check and reseat the coax and ensure that the power cord is using a wall outlet instead of a power strip of any kind. The only other thing to check without replacing the receiver or having a tech out to the home would be to replace the HDMI cable to rule our any cabling issues. If you need us to assist further please reach us on Twitter at @CoxHelp, visit us on Facebook, or email by at firstname.lastname@example.org. Provide us the name on the account with the full service address with a link to this thread so we can get started.