Chris

Well don’t spend any money on my account because I’m speculating to some extent. In essence, I’m saying that (almost) all the BBC’s HD channels broadcast from the same satellite so you can rule out dish misalignment. That would affect all the channels.

However, not all the same channels are broadcast at the same bandwidth. Some are compressed into a narrower space within a radio frequency that may be carrying half a dozen or more channels, allowing more room for other channels. Generally they give more room to channels where best quality is required, like BBC1 where their most expensive output is broadcast. So a particular frequency may carry eight channels - called a multiplex, or mux for short - but the space is not divided equally.

When the signal reaches your TV or your set top box, it has to be decompressed and displayed as a HD tv picture. The more the signal has been compressed, the harder that is to do well. Generally, a modern, expensive TV will do it better than a cheaper or older one. Any TV will find it easier to display good quality images on BBC1 because the signal for that channel is not as compressed as BBC News is (probably - remember I’m speculating a bit).

I don’t know what quality the satellite receiver in a Panasonic TV is but I suspect it is not as good as what you’d get from a dedicated Freesat set-top box. A good STB connected to your TV via an HDMI cable might well sort your problem. But don’t take my word for it, I’m not a TV installer. Perhaps you could borrow a box from a friend and test it?