Hi,

now that the problem with the blistering solder mask is fixed ( we sent the
boards back since backing them was of no use), I have another one.

Some of our assemblies have a high density of VIAs. On these products,
pretty often we get after wave some solder bubbles over the VIAs, some of
them exploded, like degassing. Since on some we see the same bubbling even
on the fiducials, I wonder if the humidity is the only one to blame, I even
wonder if there's any issue related to humidity at all.

So, what could it be? Incompatibility between flux and solder sounds
possible?

I would appreciate any input,

Ioan