Paul,
Are you experiencing this problem with the following:
All Files
All Users
All shares presented offline
This can help to determine where and how the problem may exist in your environment.
If you happen to have the CSC tool, you can use that to take a look at your local cache of data on your workstation and see what might be going on and any issues at fault. I've seen problems like this in the past, especially in contexts where you have shared machines, or users who lack Administrative access to their local machine (Independent of filer)
As an entirely local problem, you may want to try re-initializing the local CSC cache for Offline shares
How to re-initialize the offline files cache and database
At least, we'd be able to collect additional data and have somewhere to go from to help determine what might be going on and at fault.
Let us know if this helps at all, and if I come across something else I'll be sure to let you know!
Christopher