Filled the oil up to the max about a week ago and it is now just up to the minimum.

No obvious signs of a leak

First assumption was piston rings due to research but the smoke coming out the back of the car isn't black (which normally happens when it's burning oil, correct?)

Any ideas?

Thanks

Likely to be the piston rings, common issue on 16v I believe.

Yeah that's what I've read but would of thought the smoke coming out the back would be black.. as it's normally black when it burns oil hence the question :/

Burning oil is blue/grey, running too rich is black. The 16v 1.4 is known for the oil seals failing and that only ends badly sooner or later.

Before you write off the piston rings, you could do a compression test.

SN

The smoke appears to be clear.

How do you do a compression test?