The first thing you should try if you haven't already, is disconnecting the unit from power, then reconnecting it. This will reset the unit to factory defaults. The owner's manual includes other troubleshooting steps, but none that address this specific issue. It's likely that the unit needs to be repaired. Service can be provided at no charge under the 90-day factory warranty on a carry-in basis by the retailer of purchase. I hope this helps.
Regards, John Insignia™ Support
John|Social Media Specialist | Best Buy® Corporate Give Kudos if you like this post or Accept as Solution if it answers your query!