I mainly just watch a few things I record thru the week on the weekends, but to be clear; I see the following phenomenon on live TV as well.
Sometimes (not all the time) on some channels, I will have periods of the sound dropping out for about a second, usually along with a narrow strip of the picture about 1/3 down from the top also distorting during the sound drop out. When it happens, the frequency of occurrences can be as close as 3-4 minutes or so. Sometimes it's so annoying, I just give up watching (along with wondering how stupid I am to be paying $xxx a month for this 'privilege').
I only have one TV hooked up to my Motorola DCT6412/2000 (no HDMI on the box; component) that I've had since ~2007 via my receiver. This phenomena has been happening off and on for about a year, maybe two. This *never* happens when watching via my Roku nor Chromecast using the same setup; just the Moto.
The main channels affected (or the only ones I really watch) are the area NBC & Fox stations, along with BBC America, all in HD.
As I write this, I realized I've never checked the SD channel versions. Then again, mostly I'm watching recordings but if I do have to switch to SD just to avoid this issue, what indeed *am* I paying for?