(Pocket-lint) - We've known that Sony's likely to be working on a follow-up to its masterful WH-1000XM3 noise cancelling headphones for a little while - in fact, right at the end of last year an FCC filing confirmed that Sony's working on some form of WH-1000XM4.

It's a gap we're watching with interest, given that the WH-1000XM3 are right up there with our absolute favourites in the over-ear headphones market, giving some of the best comfort and performance you can possibly hope for. 

Now, it's looking like a launch of some sort might be more imminent than ever, after some leaked images emerged that purport to show the new model, along with some shots of its user manual. 

The shots show off some headphones that clearly share a lot of design touches with the XM3s that we've come to know and love, which makes sense. Sony's unlikely to be considering a total redesign given how much adulation the previous pair of headphones were greeted by. 

That means they're still a pretty hefty set of cans, doing nothing to shrink down their form factor. 

Thin on details

The user manual, pictured in some later Tweets, suggests that the headphones will add Bluetooth 5.0 for added stability on the connection side, but other technical specifications aren't detailed. 

Of course, there's also a solid chance that these pictures aren't what they seem - you've got to take image leaks like this with a healthy pinch of salt until they're more solidly confirmed. 

Writing by Max Freeman-Mills.