IPCC Monitoring and Recording Poor Voice Quality

[d.kettler]

We have CCM 3.3.4 and IPCC 3.1.3. Everything works correctly except the monitoring and recording of calls. The voice quality of the monitoring is robotic and the recordings are sped up from the original conversation. We have two recording/monitoring servers on different networks. The local IP phones and monitoring server are on the same VLAN. The server is connected to our core 6509 and the phones are connected to 3550s. The inbound calls originate across a T3 WAN link that is terminated at a 7206.. The calls are then routed by the MSFC in the 6509 to the voice vlan.

The SPAN on the 6509 is set up with the voice vlan as the source and the server port as the destination.

PSTN-r3745-sw6509-r7206-WAN-r7206-6509-3550-Phone

Thanks

Dave

[yogeswar]

Hi,

Refer the troubleshooting steps in "Service Information Cisco Desktop Product Suite",

http://www.cisco.com/univercd/cc/td/doc/product/voice/sw_ap_to/apps_3_1/english/admn_app/sinfo.pdf

Problem The sound quality is poor, and sounds choppy like a motorboat.

Solution Try this:

|Adjust the Sound Buffers registry entry. Set it higher; and if that doesn’t work set it down to 3 and work your way up.|Adjust the Jitter Buffer registry entry. It should be at least 400; try setting it higher. If that doesn’t work you may have to use a different sound card.

Also check if the agent phones are being spanned and the Gateway is also being spanned. If they are spanning the gateway have them remove spanning for it and retest.

Regards

Yogi

[d.kettler]

We have narrowed the issue down to gateways with H323 cause the issue. No MGCP gateways cause any issues

Thanks

Dave

[venkasub]

Hi,

This is typically caused by duplicate packets arriving at the VoIP server. This is usually because the agent phones are being spanned and the Gateway is also being spanned. If they are spanning the gateway have them remove spanning for it and retest. You can use Netmon on the VoIP server to check for duplicate packets being received.

Also see the troubleshooting steps in "Service Information Cisco Desktop Product Suite",

http://www.cisco.com/univercd/cc/td/doc/product/voice/sw_ap_to/apps_3_1/english/admn_app/sinfo.pdf

Problem : The sound quality is poor, and sounds choppy like a motorboat.

Solution Try this:

|Adjust the Sound Buffers registry entry. Set it higher; and if that doesn’t work set it down to 3 and work your way up.|Adjust the Jitter Buffer registry entry. It should be at least

400; try setting it higher. If that doesn’t work you may have to use a different sound card.

The IPCC Express monitors agent phones by being connected to a switch port that is spanning the agent phones with no layer 3 switching between the phones and the IPCC Express server.

See the VOIP Monitor Server 4.2 Best Practices Configuration Guide for more information on how to set up VoIP monitor/recording.

http://www.cisco.com/en/US/products/sw/custcosw/ps1001/products_tech_note09186a008010e6ba.shtml

If the above doesnt help, please open a TAC case to pursue.

Regards

Venkat

[venkasub]

Hi,

In addition ... Take a look at the below tech notes - Why Is the Voice Playback Slow and Distorted?

http://www.cisco.com/en/US/partner/products/sw/custcosw/ps1846/products_tech_note09186a00801dfeb3.shtml

Hope it helps.

Regards

Venkat

[d.kettler]

Thanks for the responses. We believe we have duplicate packets but we the source of the SPAN is the voice VLAN. The voice gateway resides across a WAN but the voice packets do enter through a data gateway connected to the 6509. I will try to see if can set the source ports to be the IP phones.

Thanks

Dave

[d.kettler]

We have set up SPAN withh the source port as one phone port and the destination as the Recording Server. We are still getting the robotic voice. This works fine if the gateway is local but we have this problem if the gateway is across the WAN. Are there any issues with having the inbound voice gateway across the WAN?

Thanks

DAve