I bleed out the speaker
As the speaker that spoke when they didn't speak
Speaker is a double entendre for speakers, i.e. stereos and a speaker, i.e. one who is speaking.
So there are two readings of this line:
1) When you hear his voice “bleeding” from the stereo speakers, he’s the person voicing a truth which no one else has the courage to say.
2) Whenever someone reiterates the ideas Kendrick expresses in his songs, it’s like he’s talking, even though he “didn’t speak.”
To help improve the meaning of these lyrics, visit "Ignorance is Bliss" by Kendrick Lamar Lyrics and leave a comment on the lyrics box