Hi Tim
There is nothing wrong/broken with your B2. The unit relies on 3rd party, web based, publicly available, services for Radio and YouTube - when these are changed, this is without Brennan's control but it can appear that the B2 is glitching.
When this happens come to the Forum and it is probable that others are reporting the problem too. Most often a fix can be found.
You say you were wanting Radio 4 - BBC Radio 4?? If so this is I think one of the stations the BBC moved -
As Mark said this is probably in a "preset" if you are selecting it form the handset.
You will need to go onto the Web UI and find BBC 4 from the Full radio menu and then when you select this and find it is working, use this good link to replace that in the
Preset.
Fred
Fred