Ping Monitor false positive

I have upgraded dude from the beginning and around 3.0 I started to get false positives on equipment I am pinging. To fix it I click the export button or stop and start the dude service. I have tried to export dude and reimport and it still does it. Does any body have a idea how to fix this???
I am currently running dude 3.5 on a windows 2008 server.
I have tried it on an xp machine and it still happens.