After reading all the negative comments elsewhere about the 'faults' with 648 signal, I thought that I would post my view of what can be heard in the middle of the target area, in Mid Suffolk (IP14).
Out in the car around midday today (16/04/23) and the signal seemed very high quality. A track was played with a bass only intro and it was clear and powerful. I then removed my car aerial to go through a car wash. Tried tuning up/down the dial. There were only two signals that it locked on 648 and 693 (Strange - 693 - as 909 is usually the dominant BBC 5 Live signal). My wife, who is usually a stern critic of 'AM crackle/pop' didn't realise that it wasn't FM.