Huawei
Enable or Disable Mono Audio auf Huawei
Mono audio is an accessibility feature on Huawei phones running EMUI. When it is active, the system combines the left and right audio channels into a single signal and sends it to both speakers or both sides of your headphones.
This is useful if you only have hearing in one ear or on one side, since no part of a stereo mix gets lost. If Mono audio switches on by accident, though, music, videos and games lose their stereo width, and everything sounds flat and centered instead of spread across left and right.
You control this option through the accessibility menu, not through the sound or media settings. Go to Open the settings ➔ Tap on Accessibility features ➔ Tap on Accessibility ➔ Activate or deactivate Mono audio.
The toggle applies system-wide. It affects built-in speakers, wired headphones and Bluetooth audio devices at the same time, so you do not need to change anything inside individual apps.
If stereo sound is still missing after you disable Mono audio, check the volume balance slider in the same accessibility menu, since an extreme left or right balance setting can produce a similar effect.