Troubleshooting guide

Trunking
113
Poor audio quality on LS
trunks on the 3300 ICP MX,
CX, or CXi platforms.
Not utilizing latest DSP
enhancements.
To improve audio quality on LS interfaces used
on the 3300 ICP MX, CX, and CXi platforms, a
new technology and DSP enhancement was
introduced in 3300 Release 6.1 UR1
(6.1.7.11_4).
This product enhancement addresses the
following audio quality issues:
• Echo at the beginning of outgoing calls via
the LS interface on the AMB and AOB
boards.
• Double-talk or choppy audio when internal
party speaks at the same time as the
external party.
Upgrade the 3300 ICP to Release 6.1.7.11_4
or later. Then, re-run the Line Measure Tool on
the embedded analog trunks. The
recommended settings suggested by the LS
Measure tool must be programmed in the trunk
circuit descriptors to activate this echo
canceller enhancement. This enhancement
applies only to the embedded analog
trunks.
Note: Set the trunk circuit to LONG before
running the Line Measure Tool. This setting is
crucial when using internal milliwatt tone,
instead of the Telco's milliwatt tone.
Poor audio quality on LS Trunk
on a UK site.
Incorrect subscriber line has
been provided by the carrier.
To ensure that the correct lines are
provisioned in the UK, ensure that the Telco
(e.g. BT), or carrier, provides trunks that are
compatible to System X line type ‘0’
(Subscriber lines) or line type ‘3’ (business
PBX/PABX lines).
Both types of lines will work satisfactorily with
the 3300 ICP, however line type
‘3’ is the preferred line type for connecting a
PBX/PABX.
LS Class trunk fails to display
or collect Calling Line
Identification (CLID) on the
embedded ASU in a 3300-MX
controller.
The ANI/DNIS/ISDN Number
Delivery Trunk option is
enabled in the COS of the
trunk. When this option is
enabled, the LS class trunk
fails to collect CLID during the
first and second ring cycle and
only the trunk label will be
displayed on the set. If this
option is enabled, it takes an
additional 5 to 12 seconds
before the call is presented to
the set.
Disable the ANI/DNIS/ISDN Number Delivery
Trunk option in the COS of the trunk.
Table 33: Troubleshooting Analog Trunks
Symptom Possible Cause Corrective Action
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