Qsys in QuartusII 14.0 can't assign base address correctly?

Hello,

I have downloaded QuartusII 14.0.When I add new instance in Qsys,the base address overlaps another instance which I added before.Then I click system -> assign base address.But the error still exists.After I change the base address by myself, there is no error in the project.There is a picture.Do you think it's a Bug in Qsys?https://www.alteraforum.com/forum/attachment.php?attachmentid=9167