I have used WMM many times without much trouble; but recently I noticed that certain files after editing have audio out of sync. Details:
1. original file is .wtv file from recorded broadcast TV channel; audio is in sync in the .wtv file.
2. after editing the file (i.e. cutting out the commercials), the audio is still in sync in the project in WMM.
3. when file is saved as either .mp4 (default), OR .wmv, the audio is out of sync, being played back in WMP. After burning to DVD, it is still out of sync in the DVD player, so I know it is the WMM conversion process saving the file.
4. mostly has this problem only with a certain TV channel KTXHDT2 (Houston, TX); audio is in sync while watching the movie, and still in sync in the .wtv file; but after saving to either .mp4 or .wmv, audio is out of sync. The last 5 movies I saved on this channel has this problem, but none recently from other channels have this problem.
5. I have all the latest, with recent updates - Windows 8.1, WMM 2012 v. 16.4.3505.0912.
6. I am saving the file in "recommended for this project" with 16x9 size, and it says pixels are 854x480.
I have seen this problem of out-of-sync audio in the past, but was an intermittent issue, and I didn't have enough data to determine where the problem was. Since every movie now saved from that one channel appears to have this problem, I was able to see that every time it was saved for each movie the audio got out of sync. I thought it might be corrupted file, but recording the same movie at a different time yields the same results, and now every movie from that channel has the issue. It appears to me like a codec issue, but I don't know which codec to isolate, since I don't know which codecs are being used in the wtv file; however, it also could be something else. I tried the "fixit" tool, but it doesn't work with 8.1.
I also discovered that if I just save the movie with NO edits (just a conversion from wtv to mp4) still gets audio out of sync. The problem is definitely in WMM. More evidence: saved the file in 1920x1080 video, same problem.
I am afraid to install k-lite codecs, since this would be an experiment, and might mess up other good codecs; I don't really want to try this unless someone tells me it will likely solve the issue.
If anyone can help me solve this problem, I would appreciate it.