Scooby Doctor

Good evening.

I appear to have a knocking coming from the N/S rear coilover, seems to be the strut itself that is knocking and not spring or top mount, i have lowered the car about another 10mm to see if it stopped, it did for a few days, but now it is back.
If you move the body you can hear a slight knocking, also there seems to be a small amount of play in the body to damper.
Ive also tried different damper settings.

Any ideas how to solve this issue pls guys?

oh the car is a 93 wrx if that will help in anyway.

Thanx in advance.