Dropped and Garbled audio with SpectraLink 8440 Phones

[steve_dreher]

I have a site with 95 SpectraLink 8440 phones and 80 APs with a ZD 3000 running 9.6.1.0.15. We experience dropped audio for up to 8 seconds and then the call will come back. The SpectraLink phone logs show very high Tx and Rx retries. I was told this ZD load addressed dropped audio issues with SpectraLink but we continue to have issues. The SpectraLink phones are at 4.3.0 which is also the latest software. The inside APs are on the 5 GHz band to reduce interference with a separate customer WiFi and the outside APs are on 2.4.

[luke_sandberg]

I checked that out, but it's for the Microsoft Lync support and we are not using that. So it looks like the latest for me is still the 4.3.0.

[matty_brown]

All that means is that the firmware additionally supports Microsoft Lync 2013. It doesn't mean that you have to be using Lync to run the firmware. See page 7 of the release notes to check if the firmware is compatible with your hardware. Ours are - yet we never asked for Lync support.

On a side note, the new firmware kind of fixes one issue and causes another. No more large packet losses, but the phones seem to have trouble handing off (roaming) to other access points.

Will these phones ever work properly?? 😞

[michael_daracz]

Hello, I would like to join this convo.   I have a zd with 16 access points. 7363s.   It seems like forcing channels on individual access points helped, but its still not perfect.   I updated to 4.6 firmware, but that made it much worse for me so I downgraded. 

[keith_redfield]

First of all, thanks everyone for contributing your experiences here - I think this is a good example of how forums like this can enhance overall resolution.

Our engineering team has been working with Spectralink on this issue. There are several contributing factors - best practice guidelines, a high number of independent variables in the environment and some software quality issues.

I have anecdotal reports from other sources that turning down the transmit power on the APs seems to help.

We also have a new version of 9.5 (9.5MR3) coming out in the next few days and that has some fixes that also look promising.

I'm not going to declare victory (yet), but I think we are getting close. We appreciate your patience while we work through this issue.

[matty_brown]

Here's hoping! Do us a favour and post something here to let us know when the new firmware is available to download! :)

I presume a new version of 9.6 will incorporate the same fixes, too?