Okay so to put it simply, I recorded a PS4 video using my Elgato HD60S, as I always do, however this specific video (.mp4) corrupted on me. I found the same video with a .TS extension in another folder.

I opened the .ts file using Windows Media Player, and the video is there, along with the audio all working. I drop it into Vegas Pro 13 and there is no audio whatsoever. Any help?