PS fluid level is spot on ( would have been good if this was the issue
)
On other forums (E90) the steering rack came up as most common issue for a similar problem. Looking to find some cross sectional drawings now to see how exactly this part works.
I have checked if there are any active "recalls" but couldn't find any.
The control arm check seems easy enough - so will do that tonight.
The other thing I would like to check is if I can find any bolts that are loose in the steering system.
I will post any findings.