QoS Degraded Uplink with 7925 Phones on 5GHz Network

[andreas.eichhorn]

Hello,

after an Upgrade from 8.0 to  8.2 or 8.3 we could see a lot of "Potential degraded QoS in downloink direction" error messages on Prime Infrasturcture (WCS) Voice Diagnostics with 7925 Phones on 5GHz Network

The Voice Quality of all calls is bad (noise etc.) with an MOS between 2.5 and 3

We did not change QoS config on Switches (Catalyst 4500 and 2960X)

We used the 8.0 Software for more than 6 years without any problems and after the upgrade the problems are starting. Is there a change in QoS staring with 8.1?

Any suggestions or help would safe my day.

Thank you

Andreas

[Scott Fella]

QoS hasn't really changed much through the year. Now is QoS the real issue or can it be something else that the upgrade might of changed that is causing voice issue to be more visible?  There are some bugs that are new on v8.2 and v8.3 that may affect RF in general that can cause issue to voice.  Right now we are running v8.2.130.0 and have noticed in one of our sites that voice quality has been better than previous v8.2.x code versions. v8.3 is still young and wouldn't really trust that, but that's me.  

Run a diff of the configuration when the controller was on v8.0 and now and see if anything has reverted back or a config line changed that may result in a negative way.

Cisco might also tell you what code works best with he 7925's and what firmware load on the phones should be.  Might be a good idea to open a TAC case so they can look into it better.

-Scott

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[Rasika Nayanajith]

Refer this video as 8.0 has some QoS behaviour changes compare to previous releases.

https://www.youtube.com/watch?v=PhmhIojaEE8

Best way to confirm is voice packets get correct marking over the air  by capturing a wireless frames (in both directions)

HTH

Rasika