Is the hop at a spoke hole or exactly opposite the valve hole (between spokes)? Are you sure it is at the weld?
I've seen a few videos of rim prodution, but usually leaving out a couple of critical steps.
If I was making the rims, there would probably be a few steps including welding. Rough machining, anealing, ring rolling, hardening, ring rolling again, then final machining & drilling (should be fine after hardening).
My guess is they tried to simplify a few steps in the process, which created rims that were close, but not perfect.
Lots of reports of things like burrs which should have been taken out during manufacturing, but weren't.
The wheels should roll OK, but you need to get back to the company that the final quality just isn't acceptable with their price/marketing.