WRSA+scan progress bar skips files.

Skips from 6% to 77% in a flash and is finished in 36 seconds.  Doing the math says only 29% are scanned.  Been happening for a while now.  Three reinstalls and a system refresh giving up all files and beginning from scratch was no fix.  Happens only on one PC of three, all centrally manages and at default .  Same software and files on all three.  Other PCs scan normally and from 67,000 to 87,000 files.  PC in mention only scans 6,700 files.  Geek Squad logged in today and said all is well.  Although I'm having no problems with PC...I know something is not right.  All run Win 10....All software updated.  Plan to get Webroot Support to log in if anyone can tell me if there is a fix for this.  Have read similar posts in the past, but don't know the outcome of their support tickets.  Any information will be helpful.