Q: How to Improve Audio Quality in the 3CX app for Android

A: There are many Android devices available on the market and it is impossible to test all devices. Therefore, we have exposed some options that can help improve audio quality for devices that are not tested.

Go to the Audio Options of your Android device. Audio options are found in “Settings > Audio options.”
Echo Cancellation: By default this should be OFF because modern devices have their own inbuilt echo cancellation (hardware based). This option is for legacy and low end devices which do not have inbuilt echo canceller.
Silence detection: Sometimes this option may be incompatible with certain phones.
Microphone Gain: If a caller’s voice is too low and that caller is using the 3CX app for Android, increasing the microphone gain will help increase the volume of the audio. Example Nexus 5, 5x and HTC One V will perform better if the gain is set to 2.
Microphone Source: Most of the devices have better quality with “Advanced mode” however some old devices prefer “Basic mode”. If the audio is crackling, troubleshoot using this option. Example HTC ONE SV has better quality with Basic.
Audio Subsystem: There are 2 types of audio accelerations - OpenSL and Java. The default option is OpenSL as most phones use this scheme. However some phones might operate better using the Java subsystem.
Samsung phones: When a bluetooth headset is connected to a Samsung smartphone, and later the headset is turned off (keeping bluetooth on Samsung ON), this will cause audio from 3CX app to be distorted. To fix this, switch off bluetooth from your Samsung smartphone and relaunch 3CX app.