Is there any way to trace changes made on payroll? 

Answer

Yes. Whenever a payroll is processed or updated, once it is saved, you can trace the changes made by using the Audit Trail feature. At the Salary Entry screen, scroll down to the bottom, you will see the word 'Audit Trail'. 

Click on '(Audit Trail)', and a pop up screen will show the record. Select the changes that you want to see and click on 'View Details'