Smartsheet bug? Time / Rounding formula error

Hi, I'm using the following formula to calculate the difference between 2 times:

=IFERROR((VALUE(LEFT([End Time]@row, FIND(":", [End Time]@row) - 1)) + VALUE(RIGHT([End Time]@row, 2)) / 60) - (VALUE(LEFT([Start Time]@row, FIND(":", [Start Time]@row) - 1)) + VALUE(RIGHT([Start Time]@row, 2)) / 60), " ")

And then using the following calculation to round down the difference following this logic:

=IFERROR(IF(Difference@row < MROUND(Difference@row, 5), MROUND((Difference@row - 5), 5), MROUND(Difference@row, 5)), " ")

However, depending on what start and end times I put in, I get different results:

The difference between the 2 times is exactly the same, yet I'm getting a different result?

Answers