Apple is set to adopt a new headphone port. A US patent  granted to Apple reveals the D-shape design of the thinner 2mm headphone port.

Dubbed a 'D jack' the new port has a tiny diameter of just 2mm rather than the current 3.5mm and could be part of a plan to make the iPhone 7 thinner.

But it will mean that anyone using headphones other than those blessed by Apple will need an adapter, which could be a little cumbersome.

Apple is repeating a cunning plan from 2012 when it changed the charging port on the iPhone 5. This left many iPhone owners unable to use their expensive speaker docks and chargers without forking out for an adapter.

The tame Apple Press is trying to spin this as "it means the iPhone 7 can be thinner" but actually it doesn't. It would give an extra two millimetres, but that is not the only thick point on a phone. Apple would have to make other components, like the camera, thinner before anyone could say that this "innovation" would result in thinner iPhones.

What is more likely is that this will be a boost for Apple's overpriced Beatz headphones.