Use software alsa and not hardware

src/sflphone.in

@@ -8,6 +8,8 @@ exec_prefix=@exec_prefix@
 LD_LIBRARY_PATH=@libdir@:${LD_LIBRARY_PATH}
 export LD_LIBRARY_PATH
 
+export PA_ALSA_PLUGHW=1
+
 message="Warning, you probably did not extract the archive in the / directory,
 you must edit this script ($0) and change SFLPHONE_DIR to the correct location.
 @libexecdir@ must contain the provided libraries."