Table out of square?

Some symptoms:

Cutting a long straight line on the Y, it appears slightly diagonal.
It ends up going slightly right towards the front of the table.

When I try to do a 2 sided cut of simple drill holes, where the 2nd side is just putting the bit in the same holes that were drilled on side 1, the bit misses the holes exactly.
It drills slightly to the right towards the front of the table.
the hole towards the back is less off the mark.

Maybe the table is out of square? I did measure diagonally from corner to corner on both sides and the measurements were not exactly the same.
Would this cause the problem?

Any thoughts?

Hey Adam,

you might be interested in this:

Is your router frame a parallelogram? Mine was!

For the machine to be rectangular (“squared”), the diagonals have to be equal, you can ensure this with a method like this. Note that the length of the Y rails on left and right have to be equal too!

This is very likely. I would check if the problem disappears after making sure the machine is accurately rectangular.