Testing DP-9871 call's sound is awfully low quality

[Emattos]

I recently received from Cisco 3 9800 models to test. After installing them and programed one for a Director, I received back from the Director who complaint about low sound quality, where he heard his callers muffling and even cutting. Same feedback from how he was heard at the other side. It is not that a call can not be completed, but being a new phone which will replace our old phones, I guess it was supposed to be at least on the same sound quality as those, if not better.

I don't know if we would need any new codec for these 9800 series or what else can be done to improve this issue.

Thank you in advance.

[Leo Laohoo]

What codec are the phones configured for?

What firmware are the phone running on?

Were the calls internal or external? 

[Emattos]

Thank you for reaching out.

Codec:      711ulaw

Firmware:   PHONEOS.3-2-1-0003-28

Calls:          Are both internal and external. Testing, I even sense the lost of sound of some digits during dialing.

Thank you,

Enrique.

[Maren Mahoney]

Is the phone using a wired or wireless connection? Is the Director using the handset or a headset, and if they are using a headset what kind is it and how is it connection (Bluetooth, USB, other)?

During a call, is the phone's call statistics showing packet loss or excessive jitter?

And (and this is the stupid one, but works more often than you might think), have you re-seated all of the cords and cables connecting the phone and it's parts?

Maren

[Emattos]

Thank you for reaching out.

1. The phone is wired connected. The Director and I testing used handset, but it happened also when trying a call on speaker.

2. Statistics don't showing any sign of congestion or issues on communications, neither excessive jitter. We unplugged the 9871 and reconnected the old 8845 and the difference was way noticeable.

3. I tried the re-seating after your suggestion, and in 2 different 9871s. Same issue.

Thank you very much,

Enrique.

[Maren Mahoney]

(Edit: Sorry... I didn't see the post where you said you were already running this firmware.)

What firmware are you running? Cisco published PHONEOS.3-2-1-0003-28 at the end of October. Because the issue exists with multiple phones of the same model, it is unlikely to be a hardware issue but could potentially be a firmware issue. Upgrade the firmware if you can.

Is the phone connecting to CUCM, Webex, other?

Maren

[Emattos]

Hey Maren,

Thank you for keeping on trying to help me.

The DP-9871 is connected to CUCM ver 15.0.1.11900-23

Thank you again,

Enrique Mattos

[Maren Mahoney · Accepted solution]

You've done all of the things that I can think of. Since an active call on the 9871 is not showing packet loss or excessive jitter, and since you are running G711 which should be solid, and since you are running the most recent firmware, and since another model phone that is identically configured and in the same switchport works fine.... I think it's time to open a TAC case.

I looked in the Bug Search Tool and there are a ton of entries for the 9871 including  CSCwn02579 which describes "obvious background noise played from phone" when on a PSTN call. (Most of the others are security-related it seems.) That doesn't match your description exactly, but it tells me that you are probably not unique.

Maren

[Nithin Eluvathingal · Accepted solution]

Open a TAC case; Cisco needs to look into this.