[asterisk-dev] "internal_timing" not working (re: SIP silence suppression)

[Bryan Field-Elliot]

We are trying to get Asterisk to behave correctly when our SIP clients
have "Silence Suppression" turn on, but are not having any luck.
Basically, there are several apps in Asterisk which won't send any
audio to the SIP client, unless the SIP client itself sends audio to
Asterisk (which it won't do if Silence Suppression is enabled and the
caller is quiet).

We think we've done everything right in terms of setup, but obviously
we're missing something. Can anyone please advise? Here are the
relevant data points:

- Asterisk version is 1.6.1 (r200516M)
- Dahdi (version 2.2.0 rc2) is installed and running. Linux module is
loaded.
- Command-line tool "dahdi_test" returns +99% accuracy
- res_timing_dahdi.so is loaded in Asterisk "modules.conf" file
- "internal_timing" is set to "yes" in Asterisk "asterisk.conf" file
- Asterisk CLI command "timing test" reports:

	Attempting to test a timer with 50 ticks per second.
	Using the 'DAHDI' timing module for this test.
	It has been 1019 milliseconds, and we got 51 timer ticks

Based upon my understanding of things, all of the above points to "go"
with respect to proper support of SIP Silence Suppression in the
client, but we're just not seeing it.

Any help would be appreciated,

Thank you,

Bryan