As stated this has nothing to do with your W-4.
Social security tax of $105.45 corresponds to gross pay for the pay period of $1684.68.
Medicare tax of $24.67 corresponds to a gross pay of $1701.38. Most of the time these two calculations should match, so that might already indicate a problem.
"FICA" is the name of the law that authorizes the deduction of taxes for social security and medicare tax. If you have social security and medicare listed separately, there should not also be a deduction for FICA. Some kind of mistake has occurred. Talk to your employer.
