Tip death on maple

I have a trident maple sapling. It grows vigorously overall (18-36” a year), but every year, starting around late May-June, some kind of fungus or insect or something, kills off all the growth tips.

The tree will then sprout side shoots, and those tips die, rinse, lather, repeat, and eventually around August or so it quits killing the tips, and the tree is finally able to produce terminal buds. It doesn’t seem to slow it‘a growth down much, but I can’t figure out what’s causing it.

The only thing I can think of is maple tip borer, but I’ve never actually seen a bug.