Chris Gray has a bit of trouble with some of the voices on Radio 4

There is no mistaking the voice of John Humphrys on Radio Four’s Today, nor that of James Naughtie, too much of which is heard on days when he is co-presenting.

With other members of the team, though, I find a problem. It was easy to recognise Sarah Montague when she was sole woman on the show. But since the arrival of another female in the shape of Mishal Husain (left), I am finding it rather hard to tell them apart and work out which of them is doing the interview.

The same applies with Justin Webb and Evan Davis, whose sweetly reasonable tones and generally right-on utterances are easily confused.

These pairings should cease.