[asterisk-users] IAX over two T1 connections bad quality

[Jerry Geis]

Help please. I have two systems on the net.
one in indiana and one in georgia.
connected with IAX. local SIP phones in each office (10 each) are cisco 
and running sip.
TDM04B card in each location has 4 local lines.
Incoming calls to each location sound fine always.
The problem is dialing between offices the call quality is BAD.

Both offices are connected to the net with T1 lines. all data.

All phones are setup ulaw 64bit. The IAX connection between the boxes is 
ulaw 64 bit.

I tried skype between the two offices and talked for 15 minutes and had 
no issue.

The machine CPU usage is running 92-97% idle most of the time.

Running asterisk 1.2.9.1 and zaptel 1.2.6.

There are switches in the mix that have voice traffic having priority.

How do I determine what is the issue here? Why is the call quality bad 
and where is
it that I can tweek.

Jerry