After the quality advice I got from you all on my previous post, I am back with another problem.
When freewheeling a strange noise is coming from the back wheel but the noise is not prevalent when I am pedalling. I can only liken the sound to the clicking I used to get when attaching a cloth peg and playing cards to the frame when I was a kid, only not quite as persistent. It gives the impression something is catching something but I have checked what I can see and it all seems to be in full working order. I have noticed when upending the bike and moving the pedals backwards very gently they actually turn the wheel (I am unsure if this is normal?). But apart from this there are no obvious signs of anything amiss and the bike rides fine.
I would just like to add that the cassette was replaced recently but the bike was ridden for a number of weeks before the problem arose.
I would like to thank you all in advance for the advice I receive.