Several seconds of silent after pickup call

Hi everyone!

First sorry for my not so good English :slight_smile:

I have now FreePBX

Recently, I have a problem.
Sometimes If someone call (internal connections) example to me, then I have several seconds (usually 6 seconds) of silent after pickup call. After that several seconds is everythink is ok (I can talk).
During that several seconds, that person who is calling to me, have signal like I didn’t pickup phone yet.

Is anyone who can help me?