MS 802.1X EAP-TLS Issues

[mheck]

We are using SecureW2 as our hosted PKI and Radius.

We rolled out wired 802.1X via MS access policies and while it works, we have seen intermittent issues where windows event logs show "The network stopped answering authentication requests." and the client PC is placed on the restricted VLAN. 

Forcing a sync with Intune seems to be enough to get it back on the authenticated vlan. 

Does anyone have experience with the same setup and has encountered similar issues? 

[PhilipDAth]

How quickly are the RADIUS servers responding to auth requests?

What does the switch logs say around the time this is happening?  Any RADIUS timeout errors?

[Brash]

Is there any trigger from the client side?
For example is it seen only after the computer is woken from sleep (or low power mode), or when it's disconnected and reconnected to network?