[Orry Verducci]

So why was BBC One HD affected? - this is our national broadcaster. I switched back to Sky News and they were fine.

Haven't yet had confirmation from those in the know, but it looks like it was a Dolby E decoding issue.

Dolby E is the format used to transport 5.1 and 7.1 audio over two standard PCM audio tracks, commonly used by remote broadcasts like yesterday's coronation. Unfortunately it's also extremely finicky. If everything's not perfect it completely drops out, and it seems that happened multiple times yesterday.

Which is why the BBC One HD broadcast, which is 5.1, had issues whereas BBC One SD and iPlayer UHD which took the stereo feed were ok.

I really feel for the Engineers involved as they no doubt would have tested it all prior to broadcast, and had all sorts of redundancy in place. Sod's law however is that it will go wrong when you really don't want it to.