Where is the volume control on these seats?

I am more into understated cars. You'd never know it by these pictures. This interior was a barrier to my purchasing the car. Over the last few weeks I've learned to like it.

In the interest of full disclosure this interior is not really as red as it looks in this picture.
The top picture has a more realistic shade of red.

I've seen the Estoril Blue version of the interior and this is the Imola Red version.

Here is a site that has all of the Z3 interior colors.
This link has many of the M Roadster interiors.