The earbuds volume is relatively light

1. if you find that the volume of the Bluetooth earbuds is very light, you can turn on and off the absolute volume of the Bluetooth in the developer option of the phone, and then reconnect the earbuds.
2. so that the volume of the earbuds and the phone will be synchronized, you can use the phone’s volume control to control the volume of the earbuds.
3. On Hongmeng and some systems, the developer option is not Bluetooth absolute volume option. Sync media volume can be turned on in your phone’s Bluetooth - Earbuds Name - Settings