Dead space sound HELP

[Charlie240sxt]

I have a 95 240sx SE came with the cd player and now has..

Pioneer premier head unit Sony inside replacements from wal mart 6 1/2s Pioneer 760watt ampPorted duel 10 inch box2 Infinity Kappa perfect 10.1 wires are highend and done and ran right

But now i have this dead sound thats under the music how do i get rid of it

[PoorManQ45]

I don't understand what you're asking.

Dead sound under the music? What the hell does that mean?