In order to compile the AllJoyn Audio Service you will do so from the core/alljoyn folder per the instructions on the wiki page: https://wiki.allseenalliance.org/develop/downloading_the_source
Next pull down the AllJoyn Audio Service into the services folder:
export AJ_ROOT=`pwd`/alljoyn
git clone https://git.allseenalliance.org/gerrit/multimedia/audio.git $AJ_ROOT/services/
Now you are ready to compile AllJoyn and the Audio Service. To do that use the following and fill in the correct values for your system with [ ] meaning optional argument:
scons BINDINGS=core,cpp SERVICES=about,audio OS=android CPU=arm ANDROID_NDK=<root of the nkd location> ANDROID_SRC=<root folder of android src> ANDROID_SDK=<root of the android sdk> [ANDROID_TARGET=<name of target if different then generic>] BUILD_SERVICES_SAMPLES=off WS=off
Now you have the liballjoyn_audio.so that you can place in the armeabi folder and you can compile the Android sample applications.
Source: https://ask.allseenalliance.org/question/154/unable-to-build-alljoyn-audio-service-framework-for-android/