Can I use the 30-pin adapter to play music on my speakers?

I have a speaker with an old iPhone 4 dock but I now have an iPhone 5s. Can I use the lightning to 30-pin adapter (http://store.apple.com/dk/product/MD823ZM/A/lightning-to-30-pin-adapter) to play music or can you only use it for charging?

Added (1). Btw, if it makes any difference, my speakers are Yamaha PDX-31http://usa.yamaha.com/products/audio-visual/desktop-audio/pdx-31_black__u/?mode=model

That adapter supports audio as well as charging, but you will have to check that the phone is still mechanically secure in the dock.