Is it possible to keep music playing normally when in a voice call on Android?

I'm using Unity's Vivox voice chat library in a game. The library's documentation says that it uses MODE_IN_COMMUNICATION on Android. When on speaker, during a voice session the volume of the game music becomes lower, and 3D sound effects seem to be weakened too. I'm not familar with Android programming. Is this an expected behaviour of Android or is the开发者_如何学Cre a way to prevent voice call from affecting music play?