I’ve heard the m33 twice at the same dealer in very informal demos. First time was horrible. Something was off. Either not working right or That device has powerful digital processing capabilities that can be used or abused.
Second time……more like it! Sounded good much as expected.
Moral of the story: One sample of anything does not necessarily tell the story.
There is no way a popular amp from a established reputable company that measures that good does a bad job. Whether one likes the sound or not is a different story. Another amp I would like to hear. Any amp has to be paired with the right speakers to deliver the goods. What the “goods” are is a very personal thing.
It’s valid to listen to something and say you didn’t like what you heard but that alone does not make it “junk”. There are lots of fine wines and cigars that some people dislike immensely