SAVI 8200 - Volume control issue w/ Bluetooth and desk phone

[2ojA-r1zP0a6Re]

I am experiencing an issue wherein my SAVI 8200 Office Series headset, connected to a W8200B base will max out the volume on Bluetooth when switching back from a phone call on my Cisco phone.  The base is connected to my PC via USB, my mobile phone via Bluetooth, and my Cisco phone via the RJ45 and headphone jack with a unified cable (sorry I don't know the proper terminology for that connection).

During the day, I listen to music from my mobile phone on the headset.  When I receive a call on my desk phone and talk with someone, the volume is normal and comfortable.  When I switch back to the Bluetooth, the volume is maxed out, so I must turn the volume wheel on the headset to turn it back down.  This is jarring if I'm not paying attention to be ready for it.

An additional observation.  When I set the volume limit on my mobile phone (the hearing protection setting), it caused the headset to revert back to max volume while I was in the process of turning it down.  I would turn the volume wheel to reduce the volume, hear the tone getting lower, then it would jump back to the limit set on the mobile phone.  If I held the wheel long enough, it would eventually turn down.  I had hoped the volume limit would make it less uncomfortable when the volume spiked, but it presented this issue, so I have disabled it so that I can more easily reduce the volume when switching calls.

This issue does not occur when toggling between Bluetooth and my PC's USB connection to the base.

I do not have the Poly/Plantronics software loaded on my PC as this is a company device, so I cannot do so.  I had confirmed the firmware was current on both the headset and base through my own home PC in the last month, hoping there was an update to solve this issue.