Under the (mechanical) front passenger seat of our 2015 L&K estate there is a black plastic carapace with two fake grills at the front (fake because they are blind, with no apertures).

The plastic moulding does not appear to move in any way - I thought it might be a storage box, but no joy. Nothing I can find about it in the owner's manual. I had thought it might be something to do with the Canton sub-woofer, but that now seems improbable. Any thoughts?

Amplifier for the canton system.

It is the Canton amplifier housing

Sounds like the Canton amp to me.

Yep. Canton amp. Can confirm same in my L&K

Amp indeed.

See the pic - thingy looks familiar?

 

Thought it might be - many thanks all.