[V 4.9.6.2, rFactor 2]
It was working fine then I was just getting the "squelch" noise at each of a message but no voice in between. The log is filled with exceptions like this for each wav file used:

21:43:11.214 : Exception BadDeviceId calling waveOutOpen playing sound C:\Users\tony_\AppData\Local\CrewChiefV4\sounds\pe rsonalisations\Tony\prefixes_and_suffixes\come_on\ 8.wav stack trace at NAudio.Wave.WaveOut.Init(IWaveProvider waveProvider)
at CrewChiefV4.Audio.SingleSound.LoadNAudioWaveOut() in c:\projects\crewchief_c_sharp\CrewChiefV4\CrewChie fV4\Audio\Sounds.cs:line 1504
at CrewChiefV4.Audio.SingleSound.PlayNAudio() in c:\projects\crewchief_c_sharp\CrewChiefV4\CrewChie fV4\Audio\Sounds.cs:line 1437

Complete log: CrewChiefErrors.zip