I found this quirky online audio poetry magazine called Pismire. They have poets call and read (or sing) their poetry for submissions. The catch is, the poems accepted are often visually (and thus aurally) complex. They scoff at the idea that some poems are "impossible" to speak:
In an introduction to the E. E. Cummings poem "l(a," The Bedford Introduction to Literature, eighth edition, a popular textbook for English composition and survey courses, states, "With the peculiar title "l(a," the poem cannot be read aloud." This is absurd...Pismire is a journal for these poems, the poems that "cannot be read aloud." If your poem demands your voice or delivery, welcome. If your poem demands the auditory experience, welcome. If your poem demands a certain skill set, such as the ability to read code or chemical formulas, welcome.
Go check it out and see/listen for yourself.