1. If it is an intermittent and probabilistic current sound problem, it may be a network problem:
Please check whether the mobile phone signal is full. If the call is interrupted intermittently in a place with weak signal or in an area with strong interference, it may be caused by a network problem, which is a normal phenomenon, please try to use it in an environment with better signal.
Please turn off the 4G switch in the settings before trying to call. If there is any improvement, it means that the current 4G network may be a newly deployed network and there is instability.
Please use a standard wired headset or turn on the speaker to talk and see if there is improvement. If there is improvement, there may be a problem with the microphone, please go to the nearby after-sales outlet for inspection.
Whether the hand position is blocking the microphone port, if the other party can't hear it, please try to get close to the microphone.
2. If the earpiece makes a "zzz" sound when the volume is high, and it has nothing to do with the network environment, the reasons may be as follows:
Too loud volume will make people feel uncomfortable, please lower the volume appropriately. Some people's voices are relatively full, and the human ear is particularly sensitive to this part of the frequency, so when talking with certain people, you may hear a slight "zzz" sound, which is more obvious for users with more sensitive ears.
For users who need to use their mobile phones in high volume scenarios (such as noisy environments) for a long time, it is recommended that you use auxiliary devices such as headphones and Bluetooth headphones to make calls.
It is recommended to enter "*#*#8613#*#*" in the dialing interface to test the single item to test whether the function of the speaker, handset, microphone and earphone is normal.
If the problem still exists after the above operations, please bring the purchase invoice to the after-sales service point for overhaul.