I just had an odd thought. You know how Matoran was technically meant to be a programming language for robots? And how before Mata Nui, the MU beings couldn't understand SM and BM beings? Is it perhaps because they "speak" Matoran in a different manner than we have been assuming this whole time?
In the storyline, Matoran was always written in English (or whatever language you received it in) so we humans could understand it. But could it be possible that various sounds from the English language have more mechanical counterparts, like clicks for "K," "C," and "X," hums for "M," and "N," and whirs for "R?" The vowels, having such a huge part of the Bionicle language, also should have some unique sound. Perhaps the structure of the symbols also have something to do with their pronunciation, like two dots could be a beep (B and W), "X" shapes could have airier sounds. (V, W, X), slashes could be sizzling sounds (S and Z), etc. Basically, how I'm picturing it, this language may sound something like a bird caught in your computer's cooling fan.
So, what do you think? Plausible at all? Completely ridiculous?