MCK pbxgateway Administrator's Manual page 195

Troubleshooting
Voice Quality Expectations
EXTenders use industry-standard voice compression methods to allow
multiple users to connect using less bandwidth. While the voice quality
should remain excellent in all circumstances, you may notice some minor
affects depending on the voice compression selected. The person you are
talking to on the other end should not notice these affects in most instances.
The G.729A algorithm only uses 8Kbps for its audio path (plus overhead). It
therefore dramatically reduces the amount of network bandwidth required to
extend multiple phones. It also provides excellent voice quality to all parties
involved in a conversation. However, this algorithm is designed to optimize
audio in the frequency range of the human voice. Tones outside of that range
may sound muffled. Also, listening to audio that has already been
compressed may sound slightly less clear. Here are some of the affects you
may notice with compressed audio:
•
Hold Music may sound less clear.
•
Dial Tone, DTMF Tones, and phone Rings may sound garbled
particularly on speakerphone. They still should function properly 100%
of the time.
•
May experience some minor echo and reduced audio clarity when calling
some Cell phones. They often already compress audio.
•
May hear some echo and notice minor delay in the conversation if calling
internationally. This is caused by the delay in providing compressed
audio and the fact that calling internationally may already introduce some
delay.
Issue 2.1 December 1999
6-24