Hello NG,

I saw the following threads discussing how to switch to RTP when a client does not support SRTP. 

https://lists.kamailio.org/pipermail/sr-users/2018-May/101341.html
https://lists.kamailio.org/pipermail/sr-users/2016-September/094457.html

There are some issues with Zoiper and Bria which also persist in the latest versions. Has anyone got it work with Zoiper and Bria? 

Thanks and regards

Markus