If wall mounting is one of your considerations - do ask an electrician to check the outlets. Upon removal of the outlet, you'll probably see where the electrical wires are routed from. Kung sa itaas, then the wires are routed above, if below, then galing sa floor, kung sa sides - then horizontal ang lay-out nyan. Yes, not 100% sure - but still consult your electrician. Kung sabihin nya clear naman - then atleast you have that option kung gusto mo magbutas sa wall or not.
But your best bet is probably just relocating some stuff around the room & opting for speaker stands nalang cguro - its safer & no boring of holes in your wall pa.