Sony looks set to upgrade its flagship true wireless range soon, with the Sony WF-1000XM4. 

A prototype of noise-canceling earbuds from Sony with the model number YY2948 has been certified by the US Federal Communication Commission and Bluetooth SIG, revealing a couple of interesting upgrades. Sony's yet-to-be-announced earphones will support Bluetooth 5.2, which could result in better battery life due to its lower-power usage and wider bandwidth to transmit data. This could also result in improvements to audio, too.

The FCC filings further reveal the earbuds sport a new MediaTek MT2822S chip, which might pack an updated digital signal processor, hardware ANC, feedforward mics, and voice prompts. It's worth noting that, by using MediaTek over Qualcomm, the Sony WF-1000XM4 might lack aptX and aptX HD support. That said, The Walkman Blog thinks the processor's higher-power consumption ratings suggest LDAC support is on board.

The documents also show a render for the earbuds' case. It seems to be slightly more round.

Sony might launch its WF-1000XM4 wireless earbuds soon with some nice upgrades photo 2

The Sony WF-1000XM4 are expected to follow the Sony WF-1000XM3 from 2019. In our review of the last set of earbuds, we noted they offer class-leading adaptive noise-cancellation tech for their size and purpose while maintaining the excellent audio performance the company's range has become known for.

Their replacement, the WF-1000XM4, first surfaced via a leak in February. With FCC documents now filed, they could be facing an imminent launch.