Glennage

Hi, could anyone please advise me as to the possible cause of a very irritating clunk clunk rattle clunk from my n/s rear suspension. Seems to be coming from top of strut when suspension is not loaded.
Have purchased new top mount, but wondered if the top of the spring housing may need replacing too.
Wondered if anybody had come up against same problem as I think its fairly common and how was fixed?
Thanks in advance.