Setup SIP-over-TLS + SRTP for voip.ms

I would like to setup SIP-over-TLS + SRTP for voip.ms.

Here are the steps I did to setup Jami on my Android phone:

  • Install Jami from F-droid
  • Create a SIP account following this post
  • Follow the Jami wiki on voip.ms for the basic configuration.
  • Go to the security options of the SIP account
  • Activate: Encrypt media streams (SRTP)
  • Activate: Use TLS Transport

What I did afterward:

  • Call 4443 to do the echo test

Expected result:

  • The call goes through
  • I can here the instructions
  • I speak and I can hear myself back.

What happened:

  • The call cuts off
  • It is written: Missed outgoing call

N.B.: When I do not encrypt, the echo test works fine.

What should I do to setup the encryption for voip.ms?