SPA 525G, phone load 7-3-5, UC520 7.0.3 - sounds like the call is occurring in a tunnel

Answered Question
Nov 18th, 2009
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We are experieincing a tunneling effect on the sound quality of 525G to 525G phone calls. The tunneling impact is significantly reduced when the conversation is between an outside line caller and 525G. Back to the tunneling sound quality between 525G and 525G on same UC520 LAN - switches are ESW 24 port PoE.

The calls between 525G sounds like the conversation is occurring in a tunnel. The tunnel effect is mitigated when the volume is maximized on the 525G phone, but still very noticeable. The 525G phone user also notices the "call in a tunnel" impact when talking with a 79xx series phone user. The 79xx phone user does not notice the "call in a tunnel" impact.

Yes, I understand this load is not in the official 7.0.3 load, but it was necessary to avoid the speakerphone feeedback issue experienced on prior 525g loads. Is this something Cisco is aware? Is this a bug or simply the way it is?

Thanks in advance.

Correct Answer by SteveOrfanos about 6 years 9 months ago

Hi All,

I have just been notified by the SBSC support team that gain levels can be adjusted on the phone GUI in version 7-4-6 firmware. I will test and let you know.

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Overall Rating: 5 (2 ratings)
MICHAEL JOHNSON Fri, 11/20/2009 - 15:53
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My TAC Case: SERVICE REQUEST:613037455

Also, for once I found another TAC case matching mine. SR 613020657 -Low volume on SPA525 phones

Anyone else want to pile on Cisco here?

My first comment, is how long will the sound problems continue with this product?

I apologize for not cutting Cisco any slack, but I'm the face to the client. They are not happy and feel they were sold a lemon. I can't defend Cisco on this one. Besides the sound quality, there are plenty of buggy softkeys and screen appearances. Just look at my recent posts.

Cisco don't beome Microsoft rushing product to market just to have product.

David Trad Fri, 11/20/2009 - 21:18
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Hi Final,

I feel your frustration, however...

Cisco don't beome Microsoft rushing product to market just to have product.

Cisco's support is second to none out there, i have tried doing support with microsoft, i would have better luck dealing with a monkey high on crack then the support MS offer over the phone, Cisco TAC is unrivelled in my opinion, and their constant effort on these forums out do any of their competitors by a long shot, i think you know that as well :) This makes their products good as a direct reflection of their supporting of their product lines.

Back onto your problem :D

For the interim whilst you are working on this problem with TAC, can you implimemt forced codecs on each ephone that the 525 is plugged into, try aLaw and uLaw and then try G-729, it could be a long shot, but if it resolves the problem untill Cisco can work out what is causing it, then you can show face with the client, this is the first thing i do, i allways try and find a work around untill the matter can be resolved, as professionals we have to work through our frustrations and focus on the outcomes.

I suspect maybe the new load has increased the Gain on the handset, a common problem i have with the SPA-942/62 phones, the difference is though those phones are totally modifiable, my suspecions though could be way off and are somewhat unfounded as i have not experienced this problem yet as i am still running them on odler firmwares.



MICHAEL JOHNSON Fri, 11/20/2009 - 21:28
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Thanks my friend. Good ideas there. I'll give them a shot. You responded faster than anyone at Cisco excluding one Cisco rep who is on this board a lot. TAC has not yet addressed my issue. My fault for making it a 3, but I have more than the poor sound issue with that phone load (and prior loads). I have a long history with the the short life of the 525G. At first the gain was not enough so we had bad feedback when making POTS calls with specific carriers, softkey problems, load hangs, phones dying after 24 hours, and now this.

I love TAC, but TAC cannot do the BUs job. The BU for this phone needs to do a better job testing the product before sending it out to market. TAC cannot fix something defective in the core. They can help with coding and work arounds.

The new small business support team is pretty good too!

Thanks again - you're a great reality check!

stacy.thompson Mon, 11/30/2009 - 13:23
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I am having several issues and complaints about the 525's as well.  I am trying to see if the latest firmware will address these issues, but thought I'd chime in on this post to let you know you're not alone. 

Items I have noticed need improvement:

1. Needs to support octo lines.

2. Needs to support extension mobility ( I think this may be on the road map or soon to be ready?)

3. Needs to cursor in the call logs Edit Dial softkey to start in front of the number, not at the end.

4. Needs volume and general call sound quality improvements- tunnel or tin can sound.

5. MWI lights are inconsistent with messages and GDM messages..sometimes they work, sometimes they don't.

That's my two cents


ericdolton Tue, 05/04/2010 - 15:01
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I am expericing the same hollow voice issue on the spa 504G phones running load 504G spa5x5-7-4-2 and CUE 7.1.3.  Any updates on a fix or workaround?

Ray Long Tue, 05/04/2010 - 23:31
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Eric, try upgrading to the latest firmware 7.4.4 and see if this helps.

Link to download (must be logged in)

See the release notes for instructions on how to use CCA to drag and drop the firmware and then do the upgrade. See Installation Notes (SCCP Version)

If you still have problems, try the handset gain adjustment. More info from another thread here

Jake London Mon, 09/27/2010 - 11:06
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We're anxious to hear when Cisco is going to address the audio quality issues with the handset path.  Similiar to the posts that we've read thus far, our customers report that their conversations sound as though they are taking place in a tunnel.  That the voice quality sounds "tinny".  In our testing, we note the same voice quality issues that they, and others on this forum are reporting.  We're using SPA504, 508, and the 525 series phones.  We're running 7.4.6m firmware and we are forcing the G711u protocol.  Our transport path is a dedicated gb LAN and we experience these issues between phones on the same LAN.  We've done a side-by-side comparison with Polycom 501 phones and the difference is night and day in favor of Polycom.

These posts go back several years but I haven't seen a good solution to the problem....just suggestions and corresponding attempts followed by frustration.  Not that this discussion is hurting for volunteers but we would certainly be on board to beta some attempt at fixing the problem.  Thanks in advance for the support.

MICHAEL JOHNSON Mon, 09/27/2010 - 11:11
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Our soultion is to never use the SPA phones again. Since we gave up on the SPA phones and have strictly focused on 79xx series, we have had no phone related issues. It seems as if you keep your SPA numbers below 10 phones, the issues are mitigated, but we will not put our firm in a position to try those phones again.

SteveOrfanos Mon, 09/27/2010 - 12:14
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Hi all,

I'm having exactly the same issue with the latest software release. Customer is complaining that they can barely be heard when calling or been called.

SupportJoey Mon, 09/27/2010 - 12:17
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Ouch.  That's painful.  We're in a similiar setup.  Our experience is that the voice quality is not necessarily bad but it's certainly different.  So, if we had a chance to set the expectations for our customers ahead of them using them, we might not have audio quality issues.  Also, has anyone noticed that while it's a different audio experience on the handset that it's a more normal audio experience on the headset/speaker phone?

SteveOrfanos Mon, 09/27/2010 - 13:40
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I also noticed that spa50x-30x-7-4-6 and spa525g-7-4-6 are available for download (current firmware 7-4-4). Has this release addressed the low volume issue or would it be advisable to adjust gain.

Appreciate your help


Correct Answer
SteveOrfanos Mon, 09/27/2010 - 18:22
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Hi All,

I have just been notified by the SBSC support team that gain levels can be adjusted on the phone GUI in version 7-4-6 firmware. I will test and let you know.