Plantronics Savi 8200 USB Headset Volume Controls

[Roth Richard]

Hi all,

I'm currently experiencing the following issue with a (usb) Plantronics Savi 8200 Office Series headset

When changing the volume via the buttons on the headset, while the volume changes on the headset itself, the change is not reflected in 'alsamixer', with the (PCM) volume level remaining unchanged from its previous value. 
However, when changing the volume via 'amixer', the change is realized on the headset. 

Has anyone used this headset with alsa or able to provide some help (maybe as simple as a missing module) to get this working?

Yocto Release: Krogoth
Alsa-lib Version: 1.1.0
Headset: Plantronics Savi 8200 Office Series

Best Regards and thank you in advance, 
Richard