Constant flash and deletes sound for second

When I plugged my Tablo into the power it began to have a flash across the screen. I continued set up and everything went good. WiFi connect, guide, external hard drive, but I still have the flash constantly and it deletes the audio for a second when it happens.

Are you by chance using the Tablo HDMI? If so, make sure the HDMI cable is plugged in securely on both ends. If it is, and this continues, try swapping the HDMI cable, and let us know if this helps!

Yes I am using Tablo HDMI. I reversed the cable and made sure it was secure but it did not help. Still flashes and interrupts audio. How do I swap out the cable? Do I need to go buy one?