--- title: Audio portion of call being dropped on On prem Cisco PBX systems description: On-Prem Cisco PBX packet size limitations dropping call packets from ALICE Calls --- [Skip to content](https://kb.alicereceptionist.com/audio-portion-of-call-being-dropped-on-on-prem-cisco-pbx-systems#main-content) English Show submenu for translations [More support](https://kb.alicereceptionist.com/kb-tickets/new?hsLang=en) [![ALICE Logo](https://kb.alicereceptionist.com/hs-fs/hubfs/dBZJfwoxBhs8Xv4tDc09c1ZxvaB63hbH_A-1.png?width=200&height=93&name=dBZJfwoxBhs8Xv4tDc09c1ZxvaB63hbH_A-1.png)](https://kb.alicereceptionist.com/?hsLang=en) - [Submit A Helpdesk Ticket](https://share.hsforms.com/1HZ-ebsN3TzWAiEUV7bCVgwrei6t) - [Tickets Listing Page](https://support.alicereceptionist.com/tickets-view?offset=0) - [Knowledgebase](https://kb.alicereceptionist.com/) - [Documentation Portal](https://kb.alicereceptionist.com/documents) - [Sign Out](https://support.alicereceptionist.com/_hcms/mem/logout) Open main navigation Close main navigation - [Submit A Helpdesk Ticket](https://share.hsforms.com/1HZ-ebsN3TzWAiEUV7bCVgwrei6t) - [Tickets Listing Page](https://support.alicereceptionist.com/tickets-view?offset=0) - [Knowledgebase](https://kb.alicereceptionist.com/) - [Documentation Portal](https://kb.alicereceptionist.com/documents) - [Sign Out](https://support.alicereceptionist.com/_hcms/mem/logout) - English Show submenu for translations - [More support](https://kb.alicereceptionist.com/kb-tickets/new) - Contact us Contact us How can we help you? - There are no suggestions because the search field is empty. 1. [ALICE Receptionist Knowledge Base](https://kb.alicereceptionist.com/?hsLang=en) 2. [Network, Firewall. & Phone System](https://kb.alicereceptionist.com/network-firewall-phone-system?hsLang=en) 3. [On-Prem PBX Resources](https://kb.alicereceptionist.com/network-firewall-phone-system?hsLang=en#on-prem-pbx-resources) May 12, 2025 # Audio portion of call being dropped on On prem Cisco PBX systems ## Calls from the ARD connect with the Cisco endpoint but then lose the audio portion of the call. This behavior can be the result of the Cisco PBX dropping the audio packets because they exceed the default maximum packet size for SIP calls.  This was common on older versions of Cisco CUCM but has been addressed in later versions of the Cisco CUCM software. This Cisco Article explains the behavior, cause, and solution. [https://www.cisco.com/c/en/us/support/docs/conferencing/telepresence-server/118345-probsol-telepresence-00.html](https://www.cisco.com/c/en/us/support/docs/conferencing/telepresence-server/118345-probsol-telepresence-00.html) The customer must make the suggested changes to configure Cisco to handle the larger packet sizes.    - [Calling](https://kb.alicereceptionist.com/calling?hsLang=en#main-content) - [Call Settings & Configuration](https://kb.alicereceptionist.com/calling?hsLang=en#call-settings-configuration) - [Call Troubleshooting](https://kb.alicereceptionist.com/calling?hsLang=en#call-troubleshooting) - [ALICE Client Softphone](https://kb.alicereceptionist.com/calling?hsLang=en#alice-client-softphone) - [Check-in](https://kb.alicereceptionist.com/check-in?hsLang=en#main-content) - [Check-in Configuration](https://kb.alicereceptionist.com/check-in?hsLang=en#check-in-configuration) - [Check-in Troubleshooting](https://kb.alicereceptionist.com/check-in?hsLang=en#check-in-troubleshooting) - [Badge Printing](https://kb.alicereceptionist.com/badge-printing?hsLang=en#main-content) - [Badge Printing Configuration](https://kb.alicereceptionist.com/badge-printing?hsLang=en#badge-printing-configuration) - [Badge Printing Troubleshooting](https://kb.alicereceptionist.com/badge-printing?hsLang=en#badge-printing-troubleshooting) - [ALICE Directory Software](https://kb.alicereceptionist.com/alice-directory-software?hsLang=en#main-content) - [Branding & Appearance](https://kb.alicereceptionist.com/alice-directory-software?hsLang=en#branding-appearance) - [Configuration Guides](https://kb.alicereceptionist.com/alice-directory-software?hsLang=en#configuration-guides) - [Directory Troubleshooting](https://kb.alicereceptionist.com/alice-directory-software?hsLang=en#directory-troubleshooting) - [AI Avatar](https://kb.alicereceptionist.com/ai-avatar?hsLang=en#main-content) - [Avatar Configuration](https://kb.alicereceptionist.com/ai-avatar?hsLang=en#avatar-configuration) - [Avatar Troubleshooting](https://kb.alicereceptionist.com/ai-avatar?hsLang=en#avatar-troubleshooting) - [Employee, Department, and Company Directory Listing](https://kb.alicereceptionist.com/employee-department-and-company-directory-listing?hsLang=en#main-content) - [Directory Listing Configuration](https://kb.alicereceptionist.com/employee-department-and-company-directory-listing?hsLang=en#directory-listing-configuration) - [Directory List Troubleshooting](https://kb.alicereceptionist.com/employee-department-and-company-directory-listing?hsLang=en#directory-list-troubleshooting) - [Accessibility & Languages](https://kb.alicereceptionist.com/accessibility-languages?hsLang=en#main-content) - [Accessibility & Language Configuration](https://kb.alicereceptionist.com/accessibility-languages?hsLang=en#accessibility-language-configuration) - [Network, Firewall. & Phone System](https://kb.alicereceptionist.com/network-firewall-phone-system?hsLang=en#main-content) - [Network & PBX Troubleshooting](https://kb.alicereceptionist.com/network-firewall-phone-system?hsLang=en#network-pbx-troubleshooting) - [ALICE Cloud Resources](https://kb.alicereceptionist.com/network-firewall-phone-system?hsLang=en#alice-cloud-resources) - [On-Prem PBX Resources](https://kb.alicereceptionist.com/network-firewall-phone-system?hsLang=en#on-prem-pbx-resources) - [Processes & Procedures](https://kb.alicereceptionist.com/processes-procedures?hsLang=en) - [Hardware Maintenance](https://kb.alicereceptionist.com/hardware-maintenance?hsLang=en#main-content) - [Touchscreen Monitor](https://kb.alicereceptionist.com/hardware-maintenance?hsLang=en#touchscreen-monitor) - [Kiosk PC / Computer Module](https://kb.alicereceptionist.com/hardware-maintenance?hsLang=en#kiosk-pc-computer-module) - [Webcam](https://kb.alicereceptionist.com/hardware-maintenance?hsLang=en#webcam) - [Handset & Speakerphone](https://kb.alicereceptionist.com/hardware-maintenance?hsLang=en#handset-speakerphone) - [Other Hardware Resources](https://kb.alicereceptionist.com/hardware-maintenance?hsLang=en#other-hardware-resources) - [Windows, 3rd Party Software, & Integrations](https://kb.alicereceptionist.com/windows-3rd-party-software-integrations?hsLang=en#main-content) - [Windows](https://kb.alicereceptionist.com/windows-3rd-party-software-integrations?hsLang=en#windows) - [Excel](https://kb.alicereceptionist.com/windows-3rd-party-software-integrations?hsLang=en#excel) - [Door Access Integration](https://kb.alicereceptionist.com/windows-3rd-party-software-integrations?hsLang=en#door-access-integration) - [Other Integrations](https://kb.alicereceptionist.com/windows-3rd-party-software-integrations?hsLang=en#other-integrations) - [ALICE Portal Administration & Reports](https://kb.alicereceptionist.com/alice-portal-administration-reports?hsLang=en#main-content) - [ALICE Portal Configuration](https://kb.alicereceptionist.com/alice-portal-administration-reports?hsLang=en#alice-portal-configuration) - [ALICE Portal Troubleshooting](https://kb.alicereceptionist.com/alice-portal-administration-reports?hsLang=en#alice-portal-troubleshooting) - [Information Kiosk Services](https://kb.alicereceptionist.com/information-kiosk-services?hsLang=en#main-content) - [Information Kiosk Configuration](https://kb.alicereceptionist.com/information-kiosk-services?hsLang=en#information-kiosk-configuration) - [Information Kiosk Troubleshooting](https://kb.alicereceptionist.com/information-kiosk-services?hsLang=en#information-kiosk-troubleshooting) - [Widgets](https://kb.alicereceptionist.com/widgets?hsLang=en) - [Submit A Helpdesk Ticket](https://share.hsforms.com/1HZ-ebsN3TzWAiEUV7bCVgwrei6t) - [Tickets Listing Page](https://support.alicereceptionist.com/tickets-view?offset=0) - [Knowledgebase](https://kb.alicereceptionist.com/) - [Documentation Portal](https://kb.alicereceptionist.com/documents) - [Sign Out](https://support.alicereceptionist.com/_hcms/mem/logout) [![ALICE-Receptionistsm](https://kb.alicereceptionist.com/hs-fs/hubfs/ALICE-Receptionistsm.png?width=200&height=94&name=ALICE-Receptionistsm.png "ALICE-Receptionistsm")](https://www.alicereceptionist.com) WinTech LLC d/b/a ALICE Receptionist 8010 W Sahara Ave., STE 160 Las Vegas, NV 89117 Phone: (702) 284-73775 [mailto:support@alicereceptionist.com](mailto:support@alicereceptionist.com) Copyright © 2024, WinTech LLC d/b/a ALICE Receptionist