Another thing you might do is
1) change the mortgage interest back to $1000, then $5000 and check line 9 of the form 1040,
2) then back to $7000 and check line 9 again...
3) what's the value of line 9 for each of those settings.
I have a suspicion you are in Std Deduction territory on the Federal tax return with the lower $$ amounts, and just don't realize it.