I have a shop-made box joint router jig. I have used it about 10 times and
it gives perfect joints.

Today I made two identical boxes at the same time; one out of quilted maple
and one of bubinga.

The bubinga is fine, just like the others. The maple is too tight. I ran
it again, but it is still too tight.
I ran them the same time on the same jig and same router bit. All four
bubinga are fine; all four maple are too tight.

I can't make any sense out of this, except that there is something weird
about quilted maple, but I can't imagine what that could even be. The maple
is air-dried, but it was dry when I bought it, and has been in my shop for
about 4 months.

Anyone make sense out of this?