Music ON Hold

My problem is that when people are in music on hold, the music appears and disappears, when this person permanence in silence or speaks.
If one is on music on hold and says for example “hello”, the musica appears and if it is shut up, this disappears when slightly you blow in micro listening the music.
I nead that the music to play continuously while the person this in hold

I probe to already reproduce with mpg123, GSM and in RAW with the RAWPLAYER and the four cases is the same.
seems a function type VAD (voice activity detection) or RTP (silenc suppression) To this problem it is added that if the person does not speak during approximately 10 seconds, asterisk hangup to him,
reason why I conclude that really is a function of asterisk.