Payroll- Discrepancy between T4 summary and Rec general totals

There is a difference between the T4 summary amounts and the payroll journal/ rec gen totals.  Also between the wages G/L account and the pay journal gross total.  Already did payroll year end.  One employee elected to pay extra each pay to inc tax.  Totalling $2100.00 for the year.  Doe this have nay bearing on anything.  I have never done that before this year and maybe I didn't set it up properly to start with.  I show an unpaid payable in the Source deductions G/L account even though we have paid according to the Rec gen report all year.

Can anyone shed some light on this?