This may not be related, but there’s a special version of an ArcSoft DLL you need to use to correctly decode mono DTS-MA tracks. If you use the wrong version, you can either get an error, or – coincidentally – audio that’s stretched out exactly three times as long as it should be. I’m thinking if a software bug happened once, it could happen again. It may even be shared or licensed code, you never know. If the mastering software for some reason uses a buggy decoder to extract the length of the audio, that could explain it.