SoundFX - ogg or native wav?

I’m optimizing a game for iOS and was wondering which is faster for audio playback. Right now my setting for most short sfx is native wav and the load type is ‘load into memroy’, is this the fastest or is there a better combination?

All about it there: http://unity3d.com/support/documentation/Manual/Audio%20Files.html

Well, all in all, keep native WAV for short sound effect and allow unity to convert to ogg or mp3 for larger files. It is recommended to always provide the file as WAV and Unity does the conversion even more if you are aiming at phones since the file would be encoded even if it is a mp3 already then encoding twice the same file and losing quality in the process.