It's not that it's rude, exactly, among Ionians, to interrupt another's "speech," or make unnecessary noises while someone is communicating with you. More like a sign of mental illness. Virtually unheard of, so to speak.
Ionians "talk" to one another by using external tympani and cord-like surfaces in their head and neck area, scraped by special appendages to produce elaborate, harmonic sounds that to human ears resemble eerie combined vocal/instrumental music. Whole paragraphs of thought can be encoded in a single "chord." An adult Ionian can "speak" continuously, in what almost sounds like a slow, discordant pavane, with a steady but free rhythm. Poetry, to them, is when speech is music; then it is both; every voicing and timbre, every tempo, every rhythm, every harmony, precisely crafted to create an artistic and emotional effect, while at the same time containing semantic content, indeed, great meaning. To Ionians, this is the highest art.
Encountering human music, Ionians are perplexed. Sometimes it seems lovely, in an otherworldly way. But so tedious. So repetitive. So limited in scope. So meaningless. Almost like a subtrack of crude emoticons to punctuate thought. Just ba-ba ta-ta, over and over again with no coherence or content, and then it usually just comes round to where it started and stops, for no reason. So curious. Interesting, but odd. Now and then, just occasionally, really beautiful, but for the most part just weird.
Human speech, to them, on the other hand, sounds like grunts and moans. Awful, brash noises that fail to cohere into any kind of harmonic or rhythmic pattern to indicate meaning. Learning to actually discern meaning in this raucous cacophony is difficult, although not impossible, for an Ionian to learn. Indeed, they can even learn to reproduce a reasonable approximation of it, a feat the inverse of which will almost certainly be beyond human beings, at least in the absence of technological augmentation.
...
Part of an occasional series of tidbits about the Ionians, a fictitious alien race I have devised to populate a "science fiction universe" I've been thinking about.