Any Cage Experts Out There???

[gha]

I have an adjustable heigo half cage in my 964RS.

The cage is either creaking or picking up a noise from under the rear wheelarch and amplifying it.

I noticed that the cage is installed on top of the carpet, is this right or should the carpet be cut?

I have tried tensioning up the cage + also the mount points but the noise is still there, as i say an annoying creak like noise.

Any ideas????
Thx,
Kevin.