Greetings.
I'm trying to set up annoncement playback for both parts of the call. I have to play the file after the connection is established. Stop_media (all) must be executed before playing
It turns out the construction:

....
block_media ("all");
play_media ("all file = / etc / kamailio / sounds / mg1.wav");

Can't find a way to do
unblock_media ("all");
after the file has finished playing.

There are no sip messages in this process. The call has already been established.