[cisco-voip] Clicking/popping noises on T1 resolved -- sort of

[Mike Armstrong]

(Originally reported in Digest Vol 7, Issue 12)

Cisco eventually decided this was an VWIC-1MFT-T1 problem (DDTS CSCec43050).
Symptoms are as described previously -- the MFT will report line errors (we
saw hundreds of thousands in a 15-minute interval) not detected by Telco
monitoring or test equipment.  This apparently occurs very rarely, and is
felt to be a Telco line-noise problem (I agree), but since the errors are
not detected by typical Telco test equipment (e.g. T-Berd), they won't be
inclined to diagnose or fix it.  The solution is to insert an OEM CSU
between the output of the HTU-R "SmartJack" and the MFT to act as a line
conditioner.  Since installing one of these, we have seen zero errors.

Mike Armstrong
University of Florida CREC
Lake Alfred, FL
863.956.5891