Let's face it, outdoor speakers are expensive, inconvenient and not the best quality, so here's a possible solution. With iTunes running on your PC/Mac, plug in an Airport Express to an outside power outlet and use Airport Utility to make sure it is extending your network. Then plug in a sound system to the speaker port of the Express. This can be as simple as a pair of headphones, a headphone radio pack if you want to go wireless, a set of powered speakers like the Monster Clarity or a 5.1 system with tower speakers. Your imagination is the limit. The remote app will allow you to control iTunes from your iPhone/iPad, so you don't need to leave the barbecue to change the sounds.