Channel Audio Missing (sometimes)

I have a Tivo Romio Plus and certain channels will at time not tune in the audio. Change the channel and change back and most of the time the issue is resolved, however it stinks when a recording is missing the audio. I have a mini connected via ethernet just as additional information. The audio tuning issue exists when watching on either the mini or the romio. Tried new cable card and as well as tuning adapter with no success. All signal levels seem to be within spec. Any suggestions would be welcome.