I have jacked the car up (both sides, to even out the forces on the ARB), and put another jack underneath the wheel to lift it to several stages of suspension load.
I tried rocking it in all directions (9/3, 12/6), nothing serious.
So whatever I try, I can't replicate the noise. I used a crow bar (with rubber pads) to try to move things, but nothing makes a sound or shows serious play. This is also what my garage did, and they found nothing as well.
The sound started about a year ago, some 2500 miles I guess, and I can't think of anything that was done to that side that might have caused it.
As the lower balljoint and wishbone look good and I feel nothing there, I am now leaning towards the shocks themselves.
When replacing the droplinks, I did not notice anything wrong with the shock bush, so maybe the issue sits higher. All 4 top nuts are tight on the wheel arch inside the engine compartiment, so it is not loose.
Thanks anyway for your thoughts and ideas.