Causes:
1. There is a problem with the playback source.
2. There is a problem with the headset firmware version.
3. There is a dirt blockage at the microphone hole.
4. There is a problem connecting to the phone.
Solutions：
1. Please try to replace other audio sources or players. Some audio sources distinguish between single and dual channels.
2. Please open “realme Link > My > Firmware Update” to check and update the firmware version of the headset. If your headset is up to date or does not support firmware upgrades, please refer to How to reset the realme earphones? to try resetting the headset and pairing again.
3. Dirt blockage at the microphone hole will affect the sound quality and volume. Please clean your earphones regularly and keep them dry.
4. Some phones can be set left and right channel volume balancing, please check the phone settings, or try another phone.
For example, realme mobile phones can be adjusted in Settings > Additional/system settings > Accessibility > Hearing > Channel volume balancing.
If the problem still exists, please bring the product and purchase certificate to the nearby realme service center.
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