Hi guys! First of all good morning! OK. I rebuild Master today. Debian 8. x64. As per instructions on https://freeswitch.org/confluence/display/FREESWITCH/FreeSWITCH+1.6+Video. Also on the same machine I build v1.4. Im testing with: Win8, Win7, 32bits and 64bits. Zoiper 3.6 lite and biz, Zoiper 3.7 lite and biz. Zoiper 3.8RC1 biz. Zoiper 3.8lite. Wireshark on all machines. All internal testing. No nat, direct netwoking, near mint default config. While testing v1.4 I can fully establish a ZRTP session. Master (FreeSWITCH Version 1.7.0+git~20150609T205846Z~2e47abc9e6~64bit (git 2e47abc 2015-06-09 20:58:46Z 64bit)) seems to be happily ignoring ZRTP Hello packages from Zoiper. Also... (and remember this is almost MINT/PLAIN default config) v1.4 seems to work MUCH faster in processing and establishing calls. Fill a jira? -- Víctor E. Medina M. Platform Architect / Chief Infrastructure +58424 291 4561 BB #79A8AFA2 @VMCibersys