Steering column?

[crashthecar]

I've been noticing a knock coming through the steering colum at slower speeds on uneven road. Could this be something in the colum or further down and just telegraphing the noise back into the cabin?
Also at higher speeds the steering wheel shudders a little when cornering under heavier load, it is a similar feeling to wheels not balanced correctly but it only happens when cornering not all the time like wheel balance...
I have just replaced the LHF strut as it was leaking pretty baddly, things feel tighter but it has had no effect on these two concerns.

Any direction on thes two would be greatly appreaciated!
Luke.