Wireless Phone Voice Stuttering and Breaking

[amitesh.pandey1]

HI all, 

I have an ssid configured for wireless IP phones on my pair of 5508 WLC. I am facing problem in Voice quality of the phone. NO consistency in voice is there. I tried replacing the phone but to no avail. here is the important setting of my ssid.

Security :- WPA2-PSK

QoS- Platinum

Broadcast SSID-enabled

DTIM period=2

No Layer 3 security

Let me know what things i need to check on WLC as well as on the switch. I have checked mls qos trust dscp through the netowrk till the access points connection. 

Many thanks in Adanvce

-Amitesh P.

[Leo Laohoo]

Security :- WPA2-PSK

If this is a Cisco wireless handset then CCKM needs to be enabled.

[Marco Matera]

i use cckm+flexconnectgroups+leap authentication without a problem and good voice quality. I have set the TPC Power Control Fix to Level 1 for 5 Ghz (1 use only 5 Ghz for Voice)

[ali aqrabawi]

can you explain in more details the issue ? 

does the issue occurred while the client is roaming ? or even while the client is in static state ? 

is there a voice gap while roaming or choppy voice ?

is the WLAN local or Central switching  ? 

[amitesh.pandey1]

Ali, 

the voice is choppy and the user is static *not* roaming. This WLAN is local/ Central Auth.

Please let me know if you require any other information.

[ali aqrabawi]

choppy voice without roaming ??!! 

then check :

1)rf issues :

  -client RSSI should be >=-67

  -SNR>25

 -PER 10%

2)QoS configuration on the wired and the wireless .

[Leo Laohoo]

Ok, if this is FlexConnect site, then what happens if you bring the phone to a local AP?

[Rasika Nayanajith]

Cross check your configuration with this deployment guide recommendations. 

http://www.cisco.com/c/dam/en/us/td/docs/voice_ip_comm/cuipph/7925g/7_0/english/deployment/guide/7925dply.pdf

Hope this is 5GHz deployment

HTH

Rasika

[gohussai]

Check the following link below for Voice Stuttering and Breaking issue.

http://www.cisco.com/c/en/us/support/docs/voice/voice-quality/30141-symptoms.html