-The vaunted noise canceler still works strangely. On the one hand, it removes all rhythmic noises (the sound of train car wheels, street noise, etc.) perfectly (but again, not all!). But human speech (especially all sorts of announcements there in the subway and at train stations, etc.) very much skips. Moreover, if you just put on headphones in a quiet room, turn on noise reduction and just clap your hands, the sound will be heard! Well, again, the noise reduction does not cope with the subway (especially old cars) (although it jams decently, subjectively by 75 percent). However, noise cancellation allows you to listen to music at half volume, no negative effects (pain in the ears, dizziness) were noticed. And for a quiet room in general, passive noise reduction may be enough.
- Another strange thing was noticed - after pairing, it clings to Bluetooth almost instantly, but there is a specific problem - you press Play on the smartphone, but the sound does not play. I have to turn off Bluetooth on the phone, and then turn it back on, after that (sometimes for the third or fourth time of such a switch), everything works as it should. The defect is "floating", sometimes it does not appear at all. Perhaps connected purely with my equipment (checked the connection with the phone and tablet).
-There is no support for the AptX codec, just like any Bluetooth headphones, there are short-term interruptions in sound (but not often, mainly in public transport). Miracles didn't happen here.