The problem with pjsip 1.0.3 that it does not feature G7221 or G729, i managed to get the G722 codec working and its pretty straight once you understand whats going on… Here is the procedure:

once you have populated the config_site.h, enable the G722 codec, here what it should look like:

#undef PJ_HAS_FLOATING_POINT
#define PJ_HAS_FLOATING_POINT 1

/* SRTP has not been ported to iPhone yet */
# undef PJMEDIA_HAS_SRTP
# define PJMEDIA_HAS_SRTP 0

/* Disable some codecs for now */
# define PJMEDIA_HAS_GSM_CODEC 1
# define PJMEDIA_HAS_L16_CODEC 0
# define PJMEDIA_HAS_ILBC_CODEC 0
# define PJMEDIA_HAS_SPEEX_CODEC 0
# define PJMEDIA_HAS_G722_CODEC 1
# define PJMEDIA_HAS_G7221_CODEC 0
# define PJMEDIA_HAS_G729_CODEC 0

after this remove the –disable-g722-codec from your compile.sh, then recompile that, this should enable the G722 codec, and then you can enable it from setting when you installed it in your iphone.

Regards
Syed Arsalan Pervez aka SAP