Suddenly, when I try to use "9" to raise or an item in build mode, the camera suddenly jumps off the property. While the item does go up, I have to scroll back to the item to continue -- using "0" to lower the item seems to work fine, but the "9" key ALWAYS jumps the camera. When I have to raise an item significantly, it's very problematic. Has anyone ever seen this happen before? If so, any ideas on how to fix it? Thanks in advance!

Have you tried it with just vanilla game (no mods or cc)

Do you push Ctrl and 9? That's how I learned to raise objects up.

I hold down the Alt button and tap 9.