Itunes won't play my Wav files

I seem to be unable to add certain .Wav files to my Itunes Library. The files refuse to play regardless of whether I drag them into the open program, do the 'file/folder add option' or simply double click them.

When I try to play them in Realplayer it tells me they may be corrupt files but they play without any problems on Windows Media Player.

How can I resolve this?

Ralph