Sony tackled several pain points of the successful WF-1000XM3 with the recently released WF-1000XM4. The somewhat cumbersome oval-shaped design was overhauled, while the Japanese concern further increased the listening time. Sony also claims that these fully wireless in-ears attenuate ambient noise better. High time for an extensive review. Does the pricey Sony WF-1000XM4 live up to the high expectations?