Before anyone asks, yes, the 'Export Audio' checkmark is ticked.
I've done this many a time and it's worked, but not this time. I have 1 Video/Audio track and 2 Audio tracks. The Audio track associate with the video is silenced, because one of the other two audio tracks is the same thing after I used Audacity to remove some noise. The original video file is 1024x740, and I'm exporting it as a 1280x720 video. Of course, the video's not the problem here. The original audio files are 44100 Hz and the export settings are 48000 Hz. Note - I've done this before and it has worked perfectly. I'm trying to export it under H.264. Is there anything I could have changed subtly and unknowingly so that it wouldn't work? Exporting audio by itself results in a 15 minute empty file.
Here's the summary:
1280x720, 29.97 fps, Progressive
VBR, 2 pass, Target 5.00 Mbps, Max 5.00 Mbps
AAC, 128 kbps, 48 kHz, Stereo
If you need more information, tell me.
The audio was in a .wav file, but again, I've used this many times. The only difference between this video and others (that I can find) is that this one had a higher resolution, and it had two extra audio tracks as opposed to one. Unfortunately, this problem is null, because my trial just ended. Thanks for all your attempted help. I'll mark you guys as helpful for your effort, but it's not truly necessary to continue trying to help.
If it is any consolation (sorry that the trial ended), a PCM/WAV @ 48KHz 16-bit, is as good as it gets. I had rather expected MP3, which can cause problems under some circumstances.
Sorry that we could not get this nailed down in time.