My Explora goes as directly as possible to the many TVs here (and that is all regularly checked / adjusted for various tech needs which makes no difference), on HDMI, composite and RF. I'm certain that factor is not related here, it is a transmitted issue. Strange, perhaps your secondary's TV auto-adjusts audio.
Although not appearing widely serious, the bug can really ruin the start of some things and has had us very annoyed at times, I'm sure many others will feel the same.
Haven't experienced any sound lagging video on the whole, that issue could be related to surround sound so it may be best to put it in its own thread in the PVR Decoders section. (We mostly stopped using surround sound years ago, found it irritating too often with the way many productions over-use or poorly use it
Happy holidays everyone, cheers!