Multiple jobs not combining on single check

We are having an issue with multiple jobs not combining on a single check. 

If the employee has two or more hourly positions, it combines as expected.

If the employee has one hourly position and a monthly paid position, they are paid separately as expected.

The issue is if the employee has a monthly position and more than one hourly position.  In this situation, the hourly positions are not combining which results in three or more checks and incorrect tax calculations.

Has anyone else experienced this?