I have a NEC 2400 PBX connecting to a Cisco 3825 via PRI Interfaces. The Cisco Router is running IOS 3825-advipservicesk9-mz.124-13b.bin. The router is acting as my VoIP Router. Inbound and Outbound call Quality is working perfect. If a digital phone connected to my PBX either transfers or conferences a external phone, the voice audio drops. I increased my DB Level on my PBX PRI's. Can I perform the same function on my Cisco Controller Interfaces?