[cisco-voip] Are there any telco guy out there?

[Voll, Scott]

I have a really weird problem.  I have a remote site that there DID's
come in at the central site.  Routes over a t1 to there phones.

Caller calls local DID and it comes in and works fine.  DID belongs to
telco A.  Now there is a second Telco (b) some 60 miles away in a
different calling area, that also has a number that forwards to the
local DID (telco a).  Some calls (not all) that come from telco b have
poor audio quality.

I called telco b and they said they just have a hard loop. So no
switching happens with them, it just gets forwarded to telco a.  The
DIDs use to be an analog line.  

Does anyone have any ideas?  I also check and these are Land Lines not
cell, or wireless.  I'm trouble shooting with cisco, but believe the
problem is outside my VoIP network.  Any ideas?

TIA

Scott