Could they have fixed something with Firmware Updates in the mean time? I remember when I first got mine when they came out, die audio via cable was really abysmal. If the Fairbuds were off even at highest volume they were too quiet. And when turned on (what really defeats the purpose of having a cable in the first place, the DSP should work passively) there was a really noticeable loud hissing sound. For me, either on or off, it was really bad and unacceptable.
I don’t know, maybe they improved it through firmware.
Either way, I hope the new revision fixes this issue properly, both in hardware as well as in firmware.