Forgot to mention : Running trunk – build 17104

From: Chris Fowler
Sent: Thursday, March 25, 2010 12:48 PM
To: 'freeswitch-users@lists.freeswitch.org'
Subject: Guidance on debugging audio glitches

Hi,

Here’s the problem I’m “hearing”:

Test Case #1

x1001 calls x1002

- Audio is rock solid

Test Case #2

x1001 calls x3001 (Conference Bridge)

x1002 calls x3001 (Conference Bridge)

- Audio is mostly perfect.  However, occasional “glitches” in the audio can be heard

Notes:

- Bypass media is switched off.  FreeSWITCH routes audio for both the bridged, and the conferenced call

- rtp-autoflush-during-bridge is “true” on Sofia profile internal.xml

- I enabled the debug trace for auto-flush in switch_rtp.c (line 1895) and see occasional auto flush of rtp packets for *both* test cases.  The glitches don’t coincide with the flushing.  In fact with flushing you can’t hear when data gets flushed (2x20ms packets).

Environment

- CentOS 5.4

- Tested on AWS EC2 Small, Medium, Large instances.  On Medium and Large CPU affinity for FreeSWITCH set to the 2^nd core.

Questions:

- What’s different between bridging a call and a conference call run through mod_conference in terms of audio processing? 

- Thoughts on how to debug this?

Thanks, Chris.