Connect - User Preferences keep resetting

We have a number of users who's User Preferences keep resetting. 

I have preference seed files set up and defined on the network. If I delete my user preferences and re-open ms or pd then they will copy those defined. However, after working for a while some users find that the pref reset to 'default preferences', losing our customisation. When checking through config variables, the prefs are reading the correct files in correct locations, yet are somehow resetting on the fly from a local copy????

getting very frustrating