On the Cisco ISR 4331 series there’s a specific order needed when installing a PVDM4-32 Voice DSP Module, and setting up the associated interfaces.
version 15.4 service timestamps debug datetime msec service timestamps log datetime msec service password-encryption no platform punt-keepalive disable-kernel-core ! ! boot-start-marker boot-end-marker ! ! vrf definition Mgmt-intf ! address-family ipv4 exit-address-family ! address-family ipv6 exit-address-family ! card type t1 0 1 ! no aaa new-model ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! subscriber templating ! multilink bundle-name authenticated ! ! ! ! isdn switch-type primary-ni ! ! ! ! ! ! ! ! ! ! ! voice-card 0/1 no watchdog ! license udi pid ISR4331/K9 sn FDO202102VQ ! ! redundancy mode none ! ! ! ! controller T1 0/1/0 framing esf clock source line primary linecode b8zs cablelength long 0db pri-group timeslots 1-24 service mgcp ! controller T1 0/1/1 framing esf linecode b8zs cablelength long 0db channel-group 0 timeslots 1-24 ! ! ! ! class-map match-any ospdQoS-Signaling-Se0/0/1:0 match protocol skinny match protocol rtcp match protocol mgcp class-map match-any ospdQoS-Voice-Se0/0/1:0 match protocol rtp audio class-map match-any ospdQoS-Inter-Video-Se0/0/1:0 match protocol rtp video ! policy-map ospdQoS-Policy-Se0/0/1:0 class ospdQoS-Voice-Se0/0/1:0 priority percent 55 set dscp ef class ospdQoS-Inter-Video-Se0/0/1:0 bandwidth remaining percent 19 set dscp af41 class ospdQoS-Signaling-Se0/0/1:0 bandwidth remaining percent 1 set dscp cs3 class class-default fair-queue policy-map AutoQoS-Policy-UnTrust class class-default fair-queue ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! interface GigabitEthernet0/0/0 description Inside Interface ip address 10.200.200.2 255.255.255.248 negotiation auto ! interface GigabitEthernet0/0/1 no ip address ip pim dense-mode negotiation auto ! interface GigabitEthernet0/0/2 no ip address negotiation auto ! interface Service-Engine0/1/0 ! interface Serial0/1/0:23 no ip address encapsulation hdlc isdn switch-type primary-ni isdn bind-l3 ccm-manager no cdp enable ! interface Serial0/1/1:0 ip address 192.168.1.1 255.255.255.0 ip pim dense-mode service-policy output ospdQoS-Policy-Se0/0/1:0 ! interface GigabitEthernet0 vrf forwarding Mgmt-intf ip address 134.186.175.224 255.255.255.0 negotiation auto ! ip forward-protocol nd no ip http server no ip http secure-server ip tftp source-interface GigabitEthernet0 ip route 0.0.0.0 0.0.0.0 10.200.200.1 ip route 165.235.42.0 255.255.255.128 10.200.200.1 ip route 165.235.42.128 255.255.255.128 192.168.1.2 ip route 192.168.100.0 255.255.255.248 10.200.200.1 ! ! ip access-list extended AutoQoS-VoIP-Control permit tcp any any eq 1720 permit tcp any any range 11000 11999 permit udp any any eq 2427 permit tcp any any eq 2428 permit tcp any any range 2000 2002 permit udp any any eq 1719 permit udp any any eq 5060 ip access-list extended AutoQoS-VoIP-RTCP permit udp any any range 16384 32767 ! ! snmp-server community ospd RO snmp-server community ospd!#123 RW ! ! control-plane ! ! voice-port 0/1/0:23 ! ! ! ! ! mgcp mgcp call-agent 165.235.42.6 service-type mgcp version 0.1 no mgcp timer receive-rtcp mgcp bind control source-interface GigabitEthernet0/0/0 mgcp bind media source-interface GigabitEthernet0/0/0 mgcp behavior rsip-range tgcp-only mgcp behavior comedia-role none mgcp behavior comedia-check-media-src disable mgcp behavior comedia-sdp-force disable ! mgcp profile default ! ! ! ccm-manager redundant-host 165.235.42.5 ccm-manager mgcp ccm-manager config server 165.235.42.5 ! ! ! line con 0 password 7 0822455D0A16 login stopbits 1 line aux 0 stopbits 1 line vty 0 4 login local line vty 5 15 password 7 00071A150754 login ! ntp master 1 ntp server 134.186.5.17 prefer ntp server 134.186.253.1 ! end