No RTP engine was found/Failed to authenticate

2016-06-13 14:50:40] ERROR[4994][C-00000009] rtp_engine.c: No RTP engine was found. Do you have one loaded?
[2016-06-13 14:50:40] NOTICE[4994][C-00000009] chan_sip.c: Failed to authenticate device ;tag=1620515219

I get the above messages in /var/log/asterisk/full when I try to call from a registered linphone to an extension on this box.

[root@ivr01 src]# asterisk -V
Asterisk 13.6.0

ivr01CLI> module show like
Module Description Use Count Status Support Level
0 modules loaded
CLI> module load
Unable to load module
Command ‘module load’ failed.
[2016-06-15 10:44:18] WARNING[30605]: loader.c:553 load_dynamic_module: Error loading module ‘’: cannot open shared object file: No such file or directory
[2016-06-15 10:44:18] WARNING[30605]: loader.c:1079 load_resource: Module ‘’ could not be loaded.

In the source directory I installed from (12.8.2, but I’m running 13.6.0), “make menuselect” shows under “resource modules” that “res_rtp_asterisk” and “res_rtp_multicast” are selected already. (I upgraded via freepbx web console.)

It appears as though res_rtp_asterisk was built against libsrtp but the library can’t be found, that’s why it’s not working. You need to determine why the library can’t be found or rebuild without SRTP support.

Do you have any pointers about where to begin?

Compare your developer libraries with the run time libraries. Remove mismatched developer libraries and re-run configure, or add the matching runtime libraries.