Poor quality of calls:
1. Please check if the volume of the device is adjusted to an acceptable comfortable level.
2. When the device is used in areas with poor signal, e.g. near high buildings or in basements, the call quality may be adversely affected.
3. When this device is used in a high call intensity period, like rush hour, call failure / poor call quality may be caused by network congestion.
If you are in an area of poor reception/signal, you may experience shorter standby time than usual. This is because your device is regularly searching for a better signal and therefore consuming battery.