Some of the recent discussions on this forum got me to thinking about some of the intermittent challenges I had with picture and audio quality.
I too had "100% Signal Quality" but was, for some channels, getting more noise and interference than I expected. Most of the time things worked quite well - especially for recording. But live TV - especially football, was the most affected.
In another post there was discussion of over-boosted signal and to remove any amplifiers - there was also mention of a filter (and a link to a UK OTA filter that seems to be unavailable from any US source).
I went ahead and purchased a Channel Master LTE filter on the chance that the signal issues might be caused by that - new towers have gone up not that far away from me in the past 6 months - as well as complete removing the amplifier.
I run a Mohu leaf antenna that's mounted to an outside wall on the second floor of the house (I use 3M velcro command strips and hide it under a quilt hung on the wall).
This change has fixed all of my issues for the HD channels I can receive - my tuner (Silicon Dust Connect Quatro) sees fewer channels, but the weak ones never worked even with the amplifier.
I hope this helps somebody else who may have the same problem -