Skype call issues - Bad device state

Hi all,

during past two weeks I have noticed increased number of incidents regards Skype for business calls. Users are complaining that suddenly the other end stops hearing them. 

We have Skype for business is running on premises, Skype client version 15.0.4927.1000

While digging in the Skype for business server reporting I find something like this:

Capture device: Headset Microphone (5- Microsoft LifeChat LX-6000) 
Capture device driver: Microsoft: 6.1.7601.18208 
Render device: Headset Earphone (5- Microsoft LifeChat LX-6000) 
Render device driver: Microsoft: 6.1.7601.18208 
Microphone glitch rate: 1 per 5 minutes 
Speaker glitch rate: 291 per 5 minutes 
Microphone timestamp drift: 0,01126528% 
Speaker timestamp drift: 0,00931025% 
Microphone timestamp error: 0,0355660505592823 ms 
Speaker timestamp error: 0,17209330201149 ms 
Echo event cause: 
Voice switch cause: Bad device state 
Echo percent send: 3,09% 
Echo percent microphone in: 11,04% 
Send signal level: -26 dBov 
Receive signal level: -21 dBov 
Send noise level: -62 dBov 
Receive nosie level: -57 dBov 
Echo return: 
Initial signal level RMS: 125,749099731445 

Capture device: Transmit (Plantronics D100-M) 
Capture device driver: Microsoft: 6.1.7601.18208 
Render device: Receive (Plantronics D100-M) 
Render device driver: Microsoft: 6.1.7601.18208 
Microphone glitch rate: 14 per 5 minutes 
Speaker glitch rate: 618 per 5 minutes 
Microphone timestamp drift: 0,00761747% 
Speaker timestamp drift: 0,00914335% 
Microphone timestamp error: 0,0629489421844482 ms 
Speaker timestamp error: 0,107901096343994 ms 
Echo event cause: 
Voice switch cause: Bad device state 
Echo percent send: 1,55% 
Echo percent microphone in: 1,55% 
Send signal level: -19 dBov 
Receive signal level: -21 dBov 
Send noise level: -70 dBov 
Receive nosie level: -57 dBov 
Echo return: 
Initial signal level RMS: -53,501651763916 

I notice that each time speaker and microphone are glitching which ends in the result 

Voice switch cause: Bad device state 

According to MS explanation

Voice switch cause:
Reason why a call had to be placed into half duplex mode in order to prevent echo. In half duplex mode, communication can travel in only one direction at a time, similar to the way users take turns when communicating with a walkie-talkie. Select one of the following:
[All]
None
Bad timestamp
Echo
DNLP (dynamic nonlinear processor)
Low complexity
Bad device state
Post-AEC echo (acoustic echo cancellation)

This explains why the user "drops out" from the call and others stop hearing him, but this not help to resolve the issue.

Each time users were using headsets certified for Skype for business (Plantronics SAVI W410, Microsoft LifeChat LX-6000), we tried updating Skype for business client, headset firmware if available, audio drivers, but the next day users return saying that problem continues to exist. 

Any ideas on how to resolve this? It would be easy to say to change the headset for the user, but when you buy certified device for $100+, then you expect things to work.