TurboTax is calculating "taxable social security" (TSS) wrong. According to the program my TSS is $6,775. But using the IRS calculation the proper amount is $15,578.

According to TurboTax my "taxable social security" is $6,775. But using the IRS calculation the proper amount is $15,578.  Which of course means the AGI for my tax return is WAY off.  I can't find anyway to fix this in the program.