What would be the problem if the menu items in a custom block stop showing up but the title of the block can still be seen?

An example: a custom block titled Members Menu has a simple html table that provides a customized list of items like the following:

Members Menu
- item1
- item2

This was working fine since the beginning but the items stopped showing up recently leaving only the title "Members Menu" visible. the only thing I could think of is I have done some upgrades from earlier releases to the latest 2.0.15. But only two sites have this problem and the rest are OK.

Would appreciate your insight on this strange problem. Thanks.

Yeah, 2.0.15 does this.

God knows why, I have the same problem with my donations block. Even if I remove all traces of it from the database and re-install it it still goes blank.

Still working on why.

thanks for your reply. would appreciate it if you could share with us your findings if you have any in the future. at the time, anyone else has encountered this problem and has a solution?