1. Frequency response. The lows are insufficiently lifted, and the center is crushed, which is why only people who enjoy swotting are able to use them in their current form. Without the use of an equalizer, it is impossible to enjoy music of a high quality. Nonetheless, if this issue is resolved, the sound quality overall is quite respectable. In addition, this is a quality of the speakers themselves, as demonstrated by the fact that even when transmitted across a wire, their sound remains unchanged.
2. Native "equalizer". If the user is an idiot in general, as the term suggests, then why does he require regular settings? Let him point his finger at the presets such as "warm," "bright," and so on.
And to manufacture at least 6-7 conventional bands (to rectify what they themselves piled up), the developers claim that this is prohibitive for "elite" users to do so.
3. The headphones are brand new with a brand new battery, and the cord is cut off when the indicator is still at 20 percent. Everything would work OK, but in order to charge them after that, you would need to remove the battery and then put it back in again, because otherwise, they would not react to the charging connection. It's not really a feature; it's more of a bug. :)