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Cisco Bug: CSCuj20464 - CUCM SW MTP drops RTP packets from Phone's BIB [IPTABLES]

Last Modified

Feb 25, 2019

Products (1)

  • Cisco Unified Communications Manager (CallManager)

Known Affected Releases

8.6(2.21900.5) 9.1(1.21020.1)

Description (partial)

Audio quality issue occurs for a call that lasts longer than 5 to 10 minutes when a software media termination point (CUCM MTP) or software conference bridge (CUCM CFB) is involved in the call where the CUCM server firewall threshold settings are activated. Every alternate packet is dropped for the inbound stream from the endpoint to the CUCM media resource, while every alternate packet for the outbound stream from the media resource would be audio data "FFFFFFFF" or "7F7F7F7F".

CUCM Software Media termination point(MTP) or CUCM software conference bridge (CFB) is involved in the call scenario where the firewall threshold settings are activated.
show network ipprefs enabled 
from the admin CLI shows that the HashLimit (max:rate) value is 4000:25/second:all for the IP Voice Media Streaming Driver RTP entry

Related Community Discussions

cucm 9.1.2 проблема с записью разговора
Приветствую. Имеем  cucm 9.1.2 в составе BE6000 и аппараты cisco 7942g. Писалка разговоров Незабудка-2 соединена по SIP транку с CUCM. Возникла следующая проблема: Через 8000 пакетов принимающий звонок телефон начинает слать в сторону системы записи 1 пакет тишины + 1 пакет звука. Соответственно, через 2 мин 40 сек фонограмма начинает записываться с искажениями. Абоненты никаких искажений в течение разговора не слышат.  Аппараты в наличии только 7942G, проверить на других нет возможности. Прошивка ...
Latest activity: Jan 24, 2014
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