Just to rule out your Denon being the problem area, test different HDMI/digital optical inputs used to connect to the HD cable box. If the audio is fine in other inputs, then you know your Denon has a faulty input. If there is no improvement in sound by doing that, try a different HDMI/digital optical cable. Sometimes cables go bad.
And if none of that fixes the problem, exchange your HD cable box for another one (will be free). Those really are all the things you can do.
I currently have my HD reciever hooled up to my HD cable box from Comcast. Within the last few months or so, the audio from the HD channels comes in and out every few seconds so you would hear every 3rd word in a conversation or every third note of music.
I did not have this problem before. I have a digital Dennon receiver. Not sure if it is a setting on my receiver or the cable box.
Thanks in advance for any help.
Rob

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