Saying something is beautiful or ugly is a value judgement, in this case a value judgement you're passing on what is usually an ethnicity's most common element:

Saying something is beautiful or ugly is a value judgement, in this case a value judgement you're passing on what is usually an ethnicity's most common element: language. And this value judgement is upon a certain ethnicity. If you were to hear that Africans tend to be uglier than Swedes, wouldn't you consider that an uncomfortable value judgement to hear? Oh, but it's just your preference. There's nothing wrong with thinking that Swedes are prettier than Africans, and nobody should be considered racist or xenophobic for making such a claim. Going back to language, if you're saying my language is ugly because of how it sounds to you, all I hear is that you don't know anything about it and you're referring to something unknown as ugly. It just seems like ignorance. As to your second point, being unaware of one's accent and being unaware of one's own timbre are completely different things.