Idle problem please help

[Jimbo]

Hi everyone I have a problem with my a8 2.8.
The idle is lumpy, the revs do not fluctuate but the engine wobbles if that makes sense. The idle is a little low but it is the same until I Rev it past 1k rpm.

The fault codes I have are
01120 camshaft adjustment 1
01121 camshaft adjustment 2

Am i rite in thinking this could be camshaft position sensors?

If so does the cam belt have to be removed to replace them?

Any other ideas will be greatly appreciated

Thanks
James