Sony's next premium true wireless earphones have leaked a couple of times before, along with some rough around the edges pics, but a latest batch of unearthed images show them in a much better light.

The Sony WF-1000XM4 in-ears have appeared in an FCC posting, signalling they have been approved by the US communications commission and therefore likely to appear soon.

They have also been shown in several pictures, including the wireless charging case.

However, this latest leak looks more official. The images look like press shots and show the black and white variants in and out of the case.

Posted on Twitter by famed leaker Evan Blass (@evleaks) they show a marked improvement over the pill-shaped design of the 1000XM3s.

The case too looks slimmer and smaller - one of the only criticisms of last year's model.

While Blass didn't post any accompanying information on the WF-1000XM4 TWS ANC in-ears, we have heard previously that the case will come with wireless charging and can even be charged on the back of an Xperia phone that supports battery share.

There's also a rumour that Sony has swapped to a Mediatek processor over the conventional Qualcomm, which could impact aptX support. However, they are said to come with LDAC playback - Sony's own lossless format.