Why not buy a pass-through wallplate? Run the Belkin from "Peachtree Nova 125SE inside of a cabinet, down through the floor, and up into the wall near the speakers." At the wall, bring the wire up and out the pass-thru plate. One continuous connection and a nice finished look.
Like this:
http://www.homedepot.com/p/CE-TECH-Flexible-Opening-Cable-Wall-Plate-White-5028-WH/203564824
Like this:
http://www.homedepot.com/p/CE-TECH-Flexible-Opening-Cable-Wall-Plate-White-5028-WH/203564824