Codec negotiation error

[morcillo]

Hi, I installed mod_bcg729 for beaglebone black and then configured 2 softphones (2 different machines using microsip) to only use codec g729. Whenever I try to make a call I get:

2018-04-17 15:19:20.234998 [ERR] switch_core_media.c:4316 a=crypto in RTP/AVP, refer to rfc3711
2018-04-17 15:19:20.234998 [ERR] mod_sofia.c:2343 CODEC NEGOTIATION ERROR. SDP:
v=0
o=- 3742115449 3742115449 IN IP4 191.4.205.68
s=pjmedia
b=AS:29
t=0 0
a=X-nat:0
m=audio 4028 RTP/AVP 18 101
c=IN IP4 191.4.205.68
b=TIAS:11800
a=rtpmap:18 G729/8000
a=rtpmap:101 telephone-event/8000
a=fmtp:101 0-16
a=rtcp:4029 IN IP4 191.4.205.68
a=ssrc:815685879 cname:500659ae00113fc8
a=crypto:1 AES_256_CM_HMAC_SHA1_80 inline:+VGCBKWeSiGXDEBX/Y0m1H+gMmyQ8OriVdK4cDzaNfrIPaGMX3T6wkdseMhiYg==
a=crypto:2 AES_256_CM_HMAC_SHA1_32 inline:ynqAMMc0Ol/nHWnuZIVOpV1z5JzBDGVoiRsF7Dlhiry445b0Swkjx4pym30LFA==
a=crypto:3 AES_CM_128_HMAC_SHA1_80 inline:GrPdW0P9dE1R653VkWBmIabzbF7dvwotIW3oFBHJ
a=crypto:4 AES_CM_128_HMAC_SHA1_32 inline:nuZrqa/Bx5m6t8tkSV97szEl8Q1D1nHJGuQYiraM

I have modified vars.xml:

I run show codecs and I can see that G.729 is available in freeswitch and is using mod_bcg729, but I still cannot make a call between these 2 softphones. Any idea what could be wrong?