cx.dll causing Sonar to constantly request reboots

I am running Comcast's version of Norton Security Suite on Win10 Pro (NSS and Win10 are current on updates).
Filename: c:\program files(x86)\common files\ffdshowex\cx.dll
Threat name: SONAR.Module!gen4

I have allowed NSS to remove this file twice after NSS security alerts.  A few minutes after reboot, I get another alert.  After each reboot, the cx.dll file is successfully removed to quarantine, but then Windows restores another copy to the original location.  I am not sure if this is a "Win10 Creator's Update" file that Norton is giving a false positive, or if it is an actual threat.

A search for cx.dll hasn't given me any clues follow other than the publisher is "MediaMall Technologies".

How do I either stop the false positives or permanently delete this file if it is harmful?