PJSIP on Raspberry Pi via ALSA

Download and extract

apt-get install build-essential automake autoconf libasound2-dev
wget https://github.com/pjsip/pjproject/archive/2.10.tar.gz
tar -xvf 2.10.tar.gz
cd pjproject-2.10

Modify pjlib/include/pj/config_site.h

#define PJMEDIA_AUDIO_DEV_HAS_ALSA 1

Compile

./configure && make dep && make
/root/pjproject-2.10/pjsip-apps/bin/pjsua-armv7l-unknown-linux-gnueabihf  --config /root/pjproject-2.10/pjsip-apps/bin/pjsip.conf