Personally I would have followed up a bit more than just one phone call and an email, but you are well within your rights as a consumer to return them. Just note that as you have read here, this isn't the norm but unfortunately it didn't apply in your case. Not making any excuses for Emotiva (I don't work for them or even currently own any gear from them) just stating some additional information readily available here. Again good luck.
I have sent multiple emails with no answers!