We had similar problems as many Android phones would not play WAV files natively, find an app called Remote Wave Free or WavPlayer ($0.99) in the Play Store and install it to play WAV files. I have heard some media players like Apollo are capable of playing them as well.
Apple and Windows phones should have no issues with playing WAV, Quicktime and WMP have the support natively built in.
If you still have some users on BlackBerry with issues try AudioPOP, it is $20 but includes a free trial, so try it first because some models don't like it, and most newer models do include WAV support natively in BB.