I would get on to the seller and complain. You buy audio equipment and it should work! If it don't, you have been ripped off. As was said, take a look, but if something has burnt out, chances are the seller knew this was an issue and offloaded to you. Did he state that it was in perfect working order? Was the amp well packaged or did you pick up? If you picked up, then he knew there was a problem. Mail order could be a bit trickier as he will say it was working when he sent it. It's his problem if something is goosed, so exercise your rights!
Just re read that you said smoke coming from speakers! Are they active speakers! If so, same as before, if passive , then gawd knows what's smokin!