My drive uses an aluminum case, but it's so small that I don't belive it offers adequate protection against interference.
The suggested forum posts were very helpful, though.
Intel's paper also helps to understand how the interference occurs.
Following the low-cost shielding idea, I also did some handiwork and wrapped some tinfoil around a similar "vitamin C" tube.
I also made a small hole on one side to fit the USB connector and plugged it into the router.
It's kind of funny, but the tinfoil really seems to work miracles!
Thank you guys for all the help.