VoIP
674 ◆Features Aspire Software Manual
Internal Gain Control
Control the VOIPU PCB’s internal echo canceller input by setting the VOIPU RX gain higher and
the Highway Gain lower. (In the figure below set *1 to +12dB and *2 to –12dB.)
Not all the sidetone can be removed from the COIU by the VOIPU PCB. The remaining sidetone
may appear as echo when heard at the IP phone. Optimizing Program 81-07-01 : CODEC Filter
Setup for Analog Trunk Ports and suppressing sidetone as much as possible may still result in
some echo being heard. This becomes more apparent when the volume of the voice level on the IP
phone is louder. This may be resolved by setting the VOIPU RX Gain higher, the Highway gain
lower and by limiting the volume on the phone (in the figure below, set the *3 and *4 options to
+12dB [*3] and –12dB [*4]).