I am developing on an IMX6 platform running Android 6. We are integrating a modem with PCM audio. The PCM audio from the modem is connected to one port of the audmux. We have the dialer app and RIL components in place and working fine. Now we are trying to seamlessly integrate the modem audio streams. From what I can see there are two ways to accomplish this. The first method look like you configure the HAL and audio policy to route the streams in and out of the media server (audioflinger), which sets up patches between modem, codec, speakers, mic, etc. The second method seems to involve handling the audio directly through the audmux and connecting the modem directly to the codec while in the call. I assume the audio policy manager would notify the hal when there are changes and that would in turn trigger updating the mux routing codec settings etc. I actually have this working except I don't have the proper Audio policy/hal setup to switch. The codec is always connected to the modem at the moment. Can someone with experience in this area tell me if I am on the right track. If not, can you point me in the right direction. Thanks!