I'm on the trial, just seeing if I like it before I buy it. Every single game I've recorded so far has had the same issue when recording AVI, MP4, or MP4 NVENC. I've set it to record multi-track audio so I can separate my microphone input. In the Action player, it only plays back video and game audio, same with Windows media player and VLC. When I put the file into Movie Studio, it will only view the two audio tracks, separated game and microphone.
PC Specs:
i5 4690k
EVGA GTX970 SC
16GB Ram
Windows 8.1
AT2020USB mic
Sony Movie Studio Platinum 13
All legitimate software except Action, which I'm still on trial.