A few questions to narrow things down:

1. Is this affecting a single user or multiple users?
2. Does it only happen on a particular computer or any computer they use?
3. How many columns is the user displaying in the client?

It's been quite a while since we had this problem, but I recall similar issues with some of our users and one possible solution, if it is user-specific, is to wipe their attributes.

1. Make sure the user is logged out completely (i.e., not just closing the client, they need to select "Sign out of repository" to ensure their session is disconnected otherwise their attributes will not actually be wiped).
2. Go into the Admin console,
3. Open the user's account properties
4. Select the Attributes tab
5. Check "Show system attributes"
6. Select all attributes (export the attributes to create a backup if you want)
7. Click Remove and Apply

When the user logs back in, they will be back to the default settings meaning they'll need to choose columns and everything again.

When they set everything back up, they should add the bare minimum number of columns and try to avoid resource-expensive "computed" values like total document size.