Why does the battery of my M100 not last for 16 hours?

The M100 can provide up to 16 hours of battery life on a single charge. Please note, however, that this time may be reduced by several factors including:

Ambient Noise Mode:
Enabling noise cancelling will deplete the battery quicker. The M100 can provide up to 16 hours of battery life with ANC disabled, and up to 10 hours of battery life with ANC enabled.

High volume levels:
Higher volumes require more power to drive the speaker inside. Reducing to a lower level can prove beneficial for your hearing and extend the use of the earbud.

Using the highest possible codec:
Using aptX Adaptive or Lossless may deplete the battery quicker as more data is being transferred between your device and the M100. If you can restrict your device to a lower codec only (AAC or SBC), you may experience longer listening time. Please note that the M100 will automatically use the highest possible codec available, and this can’t be adjusted in the app.