[cisco-voip] Dialogic SR140 T38 fax to 2921 vg problems

[Carter, Bill]

Sorry about that. accidentally hit send. I'll start over.
 
We have a fax server using the Dialogic SR140 software for fax over 
IP.  The fax server is local to the voice gateway.

About 100 outbound faxes are sent 2x a day.

The gateway is a Cisco 2921 GSR2 with IOS 15.0(1)M2.  PSTN is PRI

The gateway is configured with:
voice service voip
 fax protocol t38 ls-redundancy 0 hs-redundancy 0 fallback none
!
dial-peer voice 1 voip
 ...
fax-relay sg3-to-g3
fax nsf 000000
!
dial-peer voice 100 pots
 preference 1
 destination-pattern 81[2-9]..[2-9]......
 incoming called-number .
 direct-inward-dial
 port 0/0/1:23
 forward-digits 11

When voip dial-peers are configured with:
no fax-relay ECM disable

75% off outbound faxes fail. the 25% that succeed have very distorted/illegible pages. The test fax is a single page with every line repeating the word "test". These successful faxes have distorted text across the top 1/4 of the page.
 
When fax-relay ECM is enabled and fax rate is set to 9600, outbound success rates improve marginally. Text on the successful fax fills 100% of the page with zero distortion.
 
Any ideas?
 
~*~*~*~*~*~*~*~*~*~*
Bill Carter
Senior Business Communications Analyst
CCIE 5022
Sentinel Technologies
SNR 217.391.5015
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