Weird subform behavior (any solutions)

I have a form with a subform. In the subform a have numerous conrtols of
which a few are simple calculations (+,-,/).

The form opens on a new record.

When I goto back through the records 1 at a time, all the way to the 1st
record all is good. However, if I jump to the first record, one (and only
one) of the calculated controls calculates the 1st records in the continuous
form but none of the others. My computer goes into overdrive and slowly (and
I mean slowly) it the other record values appear????

Is there a reason for this? Is there a solution?

QB