this happens all the time with these hubs. It's not like it's some obscure part, go to your LBS and buy some locknuts. I think they're 9.5x1 but I could be wrong. Take one of your track nuts and they can put it on an axle to check the threading.

Agreed that these aren't the most bomber part in the bike industry, but it's a compromise between strength and the big, serrated design.