I have an issue with some of the weapon sound .stream files where some of the weapons (namely the Deagle along with others) where the wwise_ima_adpcm.exe won't convert to .wav and instead crashes when it meets a certain file. I get the error: 
Unhandled Exception: System.IndexOutOfRangeException: Index was outside the bounds of the array. at wwise_ima_adpcm.Program.Main<String[] args>