[Asterisk-Users] Delay on zap channel

[Stefano Arata]

I'm using Asterisk on a system described as below:
Asterisk version 1.0.5
on Linux Debian version 3.0 (unstable) with kernel version 2.6.10
(hardware: PC, i386 class).
My Asterisk works with a phone card Digium TDM400P, where
2 FXS and 2 FX0 modules are provided.
It works, but I notice an annoying delay on incoming calls
from analog phones: system answers only after about 2 seconds,
even if the first command is "answer()".
If I request an external line and therefore I dial "0",
I have to wait 2 seconds to listen to the external line tones
and to be allowed to dial an external telephone number.
Asterisk should answer and give external line free tones
immediately, instead.
This issue happens on incoming calls from local internal phones,
that is from classic phones connected to FXS modules.
How can this be fixed?
Is it possible to have Asterisk answering (almost) immediately
when it receives a dial tone for the first digit?
Note that my Linux box is not overloaded: there is no possible
latency due to system performance.

More, I cannot set on hold my active calls by using the "R" button.
The only way to put on hold an active call is to hang up for
a very short time.
How can I configure Asterisk to understand my phone's "R" button,
so that it puts on hold current active voice call?

Thank you in advance,
                        Stefano Arata
                        Italy