[pbx_loopback.so]Dec 16 21:30:21 WARNING[647]: loader.c:258 ast_load_resource:/usr/lib/asterisk/modules/pbx_loopback.so: Undefined symbol "pbx_substitute_variables_varshead"
Dec 16 21:30:21 WARNING[647]: loader.c:440 load_modules: Loading module pbx_loopback.so failed!
Ouch ... error while writing audio data: : Broken pipe