Odd Call Quality Issue

[1stbyte]

Hi all,

We have a strange issue with intermittent call quality issues. We have a Fusion installation with about 30 Yealink T46S phones running the latest firmware. About half of the users say that some (not all) of their calls become 'choppy' during the call. I have listened to some of the call recordings, and the calls sound fine at both ends. The only way you can tell from the recording they are having issues is because they're asking each other to repeat what they said. It happens on inbound, outbound and internal. Has anyone come across anything like this before?

 

[Adrian Fretwell]

It sounds like RTP packet loss or excessive delay on the legs from PBX to phone. Also some mechanisms are more tolerant of delay (jitter) than others, for example a phone may discard a packet that has too much jitter but it may be still usable to assemble a call recording.

In situations like these often the only way of properly diagnosing is to run packet captures at both the PBX and the customers premises and compare the findings.