I'm inclined to use multi gang power strips with over currant protection. There are many different ones available and they can be mounted on the baseboard with the floor supporting the cables, others sit on the floor, some with covers to duct multiple feeds.
Common residential receptacles are fed from a 15 or 20 amp circuit so be careful of the load multiple devices connect to each circuit. Most sound systems will not require more than one or two 20 amp circuits. Remember, in a residence there are usually multiple, up to 8, receptacle outlets per room that may also add load to the receptacle circuit you are using. Another option might be to replace the plugs with side wired plugs that will allow the cord to run in various directions close to the wall.
Commercial applications can be designed to provide multiple circuits adapted to heavy load requirements and cable support doesn't have to be as aesthetically pleasing.
