Right, but that assumes the culprit is the device or the chipset. So, if it drains the N900 ~1500 mAh battery in an hour, it will probably drain a bigger phone battery in two hours (from full), assuming the non-USB consuption are about the same on both phones. A laptop would likewise be drained quickly. Now, assuming laptops (for sure) and tablets and phones (probably) are target market for these devices; does the maker actually expect the adapters to sell?

Looking around the web, I don't see any reviews mentioning power consumption being a problem, or evaluating it in any depth. So we still don't know what exactly is causing the drain; since that's the case, it's more difficult to begin to solve it.

But yeah, one way to see if it's really the adapter that's to blame is to try a different adapter. Note that's what I did with Plugable vs. Trendent. But ordering and returning can only be done so many times. Ok, I'll see if I can try a third device, this time an older one.