And I'm mouthless, which means I'm soundless

from Lupe Fiasco (Ft. Gemini) – Dumb it Down Lyrics on Rap Genius

Meaning

A continuation of his sensory deprivation at the start of verse 1: Lupe is dumb now! (get it get it??)

What Lupe means is he has no commercial mouth: fans stuck on commercialized rap will rarely, if ever, hear Lupe on the radio..

Lupe does have a (literal) mouth:

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