Can't choose different model group to insert

[jvaca]

We have a project in the office in which the team cannot choose a different model group to place besides a water outlet. When inserting a model group, and selecting any other model group to place, revit will stall for a second, then switches back to the water outlet.

The working around is to place the water outlet group, then switch it after it is inserted to the group needed.

Anyone know why this would be?

Thanks,

Jose