Send them back, a “quick true” up isn’t all that’s required if your description is accurate but they’ll know that when they get them back and – based on my own experience – fix them for you.
Qc is a bit hit and miss, though more hit than miss these days judging from the increasingly positive reports when a few years back it would all have been of the “you’ll die in a ball of flames” variety.
As for not immediately saying “OMG that sounds terrible, let me get you a cup of sweet tea, and we’ll get someone round to collect, fix and return them whilst you get over your ordeal” if the problems with kit were as bad as described by [anyone’s] customers on a regular basis I think the world would long since have ended, so yes “send it back” and we’ll take a look is about right, plenty of time for contrition after they’ve established it’s actually a build problem not cack handed spannering/abuse and really is bad not just not quite right and hyperbole.