Why do some devices feel poor in sound quality after connecting to headphones?

Solution:

It may be a problem with audio and video resources , abnormal device decoding or software configuration (such as tuning/equalizer). Please refer to the following ideas for processing.
① Whether it is due to the equipment, please change another mobile phone to play music to check whether the sound quality is normal.
②Whether the equalizer is modified or not, turn off the equalizer that comes with the software.
③Turn off the phone " Dolby Atmos® " (search for " Dolby " at the top of the phone settings interface to find the option).
Some mobile phones have built-in Dolby Atmos® tuning function, which may have negative effects when superimposed with the headset function. (MIUI system is optimizing for this situation)