I have a Focus UC which suddenly started changing volume on its own. It will be working fine, and then all of a sudden ramp the volume to maximum (or minimum). It acts as if the switch was stuck. If I try to change the volume back, it will fight me. Power cycling the headset sometimes fixes this.
I am getting sick of this. I haven't had the headset for even a year and it is acting up.
I looked at the support section, but do not see any option to update firmware. I see the release notes, but no download. But I suspect the hardware is faulty and firmware will not help. I figure that I will ask here to see if this is a common issue, and if there is a fix that I'm not aware of.
I've just started having this same issue recently as well. I killed all the Plantronics software processes and the issues persists so I don't think it's related to software. I unplug the headset dongle and the issues goes away so something with the headset for sure.