Updating calc worksheets in text documents changes font size

I have managed to insert calc worksheets into my text documents from existing calc worksheets (using insert object, OLE, worksheet, existing). When I update my text documents for changes to my worksheets, the font size changes. Then when I open the corresponding calc worksheets, I notice the zoom has changed also. How to be rid of this problem?

What is the zoom level it changes to? Will it stay permanent if you start with this zoom level?

Actually, every time I open my document file and update to latest changes in my worksheet, the size will change again (some times smaller, some times larger). Many times it maxes out to 400%, other times I have seen 98%, and less.