The 1040X is just a corrected 1040, it doesnt add anything without you entering it.  What are you amending for?

Just adding dividends and capital gains from statement received....they are married filing joint. 

Have double checked figures...entered correctly. 

?

Client received 1099 statements for interest income, capital gains, etc. after original 1040 was filed.

Are you importing the form or entering it manually?

Entering figures manually. 

Im not sure how a figure would be doubled if youre only entering it once. 

Are you sure you are not input a statement that is already on the original return? 

When entering figures directly from 1099 statement when looking at 1040X it doubles the figures I entered. 

May override incorrect amount and file by mail.

Welcome any suggestions.

Client received statement after the original form was filed, so no duplication there.

So when you enter additional interest of $100, you look at Column B of the 1040X and it shows a $200 change?