Richard,
First, I assume these are component holes?
If so, can you perform hand rework until the cause is
identified and resolved?
If you can't then I'd agree it is a huge problem.
4 - 5 holes per board, okay are these in the same general
area? Widely scattered?
Is the entire hole non-plated? Has the copper wetted at
all?
Do you have extra boards? What does the copper look like on
those? Is it discolored or uneven in appearance?
Can't say with certainty
that it's one problem, not with the info provided. Also, can't tell you how to
solve it for the same reason.
I'll try to assist but I need more info, see if you can
provide answers to the questions above, I'll do what I can.
Regards,
Franklin D Asbell
Network Circuits, Inc.
Irving, Texas