Just thought I'd share a recent experience with my almost six year old Voyager Legend headset, which has served me very well (and I recently replaced the battery in) and in case if anyone else is having a similar problem, you can try what I discovered.
Product ID for my affected headset is 0115.
You may find that upgrading the firmware in PLT Hub Desktop to v.110 will result in an earpiece that has the following symptoms:
1) Media plays through just fine
2) Calls are completely impossible, as you repeatedly hear the customary three beeps at the beginning of the call for the entire duration of the call. To take it a step further, pressing the action button on the mic arm to mute results in the "Mute On" voice message also being repeated ad infinitum.
Performing a three-button reset and unpairing the headset from the smartphone (and restarting the smartphone) does not resolve the issue. Nor does the two-button reset (the call and action buttons) to reset the headset's internal config to its defaults resolve the matter, even after several resets.
However, I was able to downgrade the firmware back to v.109 after finding where Poly keep the respective.zip file on their website host with the various language dfu files contained in it (because whenever you change the language of your headset, it's a firmware flash with the selected language).
PLT Hub Desktop has the ability to use a local file for performing a firmware upgrade/flash in its "About" menu. In this case, the file in question is named Legend_PID0115_V0109_PUBLISH_FILE.zip. After downgrading it, the problem still persisted but then it was a matter of turning off the headset, performing the two-button reset and the problem was fixed.
I tested the theory by once again upgrading back to v.110 and the fault reappeared. However, upon downgrading and resetting, the problem was still there. It took two more two-button reset attempts before the issue was finally cleared and functionality was restored, so a total of three two-button resets were performed (with the headset switched off) to successfully restore functionality.
Once restored, you can safely use PLT Hub Desktop or your phone app to set up your headset's features again. This is true for PLT Hub Desktop v3.24.0, which is what I was using on a Windows 10 PC.
So the summary of the fix is:
1) Downgrade to firmware v.109
2) While the headset is switched off, perform two-button reset - this may need to be done several times before the issue is resolved, so do not be quick to give up!
I appreciate that v.110 is meant to be a security fix that addresses two particular Bluetooth security flaws but I prefer my headset working reliably and frankly, I don't like being wasteful, throwing away technology that can still fulfill its purpose, even if it is six years later. Speaking for myself, I don't feel the security flaw is a major issue in my daily usage, so I'll stick to running v.109 from here on in and I would suggest to others that you do the same, once you understand the security implications in doing so.
Welcome to Poly Community.
Any new FW is rolled out upon internal testing done by our software quality assurance team. Plus, it is strongly recommended by our engineering to test issues using the latest firmware on device/s as new firmware often bring bug fixes and performance enhancements so that you can use your device up to its full potential as per the product design/implications. However, sometimes a firmware update/upgrade may not go as planned and one might encounter unwanted issues but that does not mean a firmware update is flawed. It could be very much down to the device itself (age of unit i.e the older the device it very likely it will develop hardware issues but not necessarily to stop one from updating FW, already existing hardware issues like faulty mic/speaker, poor battery health or some other failed component) and it is a coincidence that you upgraded at the same time hoping it will mitigate the existing issues on hardware. Sometimes issues can occur if proper firmware upgrade instructions were not followed by user/s.
We appreciate you for sharing your experience however, this is at users own risk and not recommended by Poly Support.
Since there is nothing more to add I will close this post.
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The title Admin is a community setting and does not reflect my role. I am just a simple volunteer in the community like everybody else. This forum replies or post is based upon my personal experience and does not reflect the opinion or view of my employer. Poly employee participation within this community is not mandatory and any post or FAQ article provided by myself is done either during my working hours or outside working hours, in my private time, and may be answered on weekends, bank holidays or personal holidays.