Meetme and dtmf problem

Hello everyone,
One of the Asterisk PBX (1.6.2 centosS 5.6 32bit) I manage have some problem with MeetMe.

Often I see, from the CLI, which under-pin input, Asterisk does not hear all the tones, I’ll give you an example.

I like the room number 1906, of ten members at least two or three have to try two or three times because, although put the pin correctly, I see that Asterisk CLI feels like pins 109 or 19006 oppre 19 and so on.

I assure you that press on the phone properly.

I also added the option F, but nothing has changed …

Here are my configurations

extensions.conf
exten => _numero_tel_callconference, 1, Answer
exten => _numero_tel_callconference, n, GotoifTime (08:00-20:00, mon-fri,,? s 3: s, 4)
exten => s, 3, Goto (conferences)
exten => s, 4, Hangup ()

[conferences]
exten => s, 1, MeetMe (, MCIF)
exten => s, n, Hangup ()

Meetme.conf

[general]

[rooms]

conf => 1906

conf => 2301

conf => 8924

greetings

David