Hello,
I’m hoping someone can shed some light on these silent calls issue that occurs globally through our contact centre, this has now been going on for just over 2 years with 3rd party venders getting involved, Mitel MSPs and internally reviewing our network and settings.
The sporadic issue we get (using the Micollab SIP application with the Ignite web dashboard open) the agent will accept calls and either the customer cannot hear the agent, or vice versa the agent cannot hear the customer. Below are several attempts at eliminating this issue but we are now clutching at straws.
- Replacement headsets/ different brands headsets (USB A&C)
Made changes to user’s audio settings / preferences advised by MITEL MSP (exclusive mode/ hardware acceleration/audio enhancements)
Installed all latest BIOS/Chipset software/ drivers
Replaced laptop (tested with different brand laptop Dell/HP)
Created isolated image with just Mitel software on (issue occurs on win10 & 11)
Installed different audio drivers/software, including direct drivers for headsets being used, also any sound filter/processing tools to see if any difference
Created new AD accounts/ Mitel accounts
MIVB server has been rebooted – completed by MITEL MSP
SIP MBG server has been rebooted - completed by MITEL MSP
MITEL MSP hard coded system to G711 codec (it was suggested that they are seeing a lot of discarding RTP with unallowed codec)
MiCC server upgrade 9.4.1 / Micollab software upgrade (9.8.112)
Silent calls are replicable across office network and VPN
Physical Mitel desk phones configured and tested (issues still occur)
Multiple traces sent (Wireshark)and captured by MITEL MSP but cannot locate any example
Our network MSP confirmed SIP AGL was disabled per Mitel MSP suggestion
The only unofficial fix we have is to completely remove any audio drivers and USB bus drivers and asking the user to reboot, although this is only bandage for some, the silent call issue can return on the next call or after several. - TO NOTE - out of curiosity if the agent receives a silent call if they make a call through MS TEAMS or other means the audio between both parties are fine.
Any suggestions or input would highly be appreciated!!