Take a packet capture of your VoIP segment and verify that the SDP is correct and that the RTP is making it to the correct places. If all that looks good and this is a straight out quality problem, then you need to figure out if it's happening on the voip side or on the TDM side. You should make calls (with captures) VoIP to Voip passing the media through your asterisk and also try routing a tdm call in and back out. If you have the equipment, take a mos score of the TDM loop.
Without any of the above, you will not be able to isolate the issue. -------------------------------------------------- Salvatore Giudice [EMAIL PROTECTED] VoIP Security Training, LLC http://VoIPSecurityTraining.com 848 N. Rainbow Blvd. #1676 Las Vegas, NV 89107 Phone: (617) 959-7625 Fax: (214) 279-2906 -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Veselin Kantsev Sent: Friday, November 30, 2007 2:47 PM To: asterisk-users@lists.digium.com Subject: [asterisk-users] Outgoing PSTN calls , unusable voice quality Hello, I have an Asterisk running with a Sangoma A200 card with Hardware Echo cancelling connected to the UK PSTN. If a PSTN call comes in, voice both ways is OK, however if an outgoing call over the PSTN is made I can hear the other party OK but they can not, they can barely understand what I am saying, my voice is unclear fading and skipping. Internal SIP and IAX2 calls are OK, incoming/outgoing calls over IAX2 are OK too. I've tried gsm/ulaw/alaw codecs so far. Tried disabling the echo cancelling as well. Any suggestions will be greatly appreciated. Regards, Veselin _______________________________________________ --Bandwidth and Colocation Provided by http://www.api-digital.com-- asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users _______________________________________________ --Bandwidth and Colocation Provided by http://www.api-digital.com-- asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users