3 Replies Latest reply on Mar 25, 2008 5:10 PM by Captiv8r

    Imported audio slows down or repeats

    JimAtANI
      Well, here I am again...upgraded to Captivate 3 on a powerful desktop machine and I'm having the same audio issues I had with Captivate 2 on a laptop. What's the secret to importing WAV or MP3 files so they don't slow down or repeat themselves on every slide?

      The audio files were recorded in a studio and output as AIFF files. I convert them to WAV and MP3 and have tried various settings for the conversion and in Captivate when publishing. Nothing works...

      If I use MP3 files in Captivate, they come out slightly slowed down when published (no matter what setting I use), so that the narrator's voice has dropped an octave and is speaking slower than the original audio file. If I use WAV files and publish them, they sound great but the same audio file repeats on every slide, no matter what audio I had placed on the slide.

      Can anyone help? I've asked this question before and no one seemed to know what I was talking about or couldn't offer a solution. How in the world does anyone get Captivate's audio to play properly when published?

      Thanks (and keeping my fingers crossed),

      Jim
        • 1. Re: Imported audio slows down or repeats
          Molly1*
          I am having the same problem with the MP3 files. Does anyone know a solution or work-around for this?
          • 2. Re: Imported audio slows down or repeats
            JimAtANI Level 1
            I THINK I've solved this problem. The culprit seems to be not maintaining the same sample rate and encoder bitrate when converting the audio file among formats. I started with AIFF files with a sample rate of 48.000 kHz. I edited them as needed and then resaved them (still as AIFF files) at a sample rate of 44.100 kHz. I used Final Cut Pro to do this but any good audio editor will work (WavePad is an inexpensive and really good choice on the Windows platform). Then I normalized the audio files and applied noise reduction using WavePad (basically applying some additional filters to make the file sound better), then resaved the file as an MP3 file, with a Constant Bit Rate of 98 kbps (don't use Variable Bit Rate ... Captivate can't handle it...this is one of things I've found led to slowed down audio or audio being repeated). I also used a setting that made the MP3 file Mono (my original files were stereo but Captivate doesn't seem to like stereo). So now, after importing the MP3 file into Captivate, don't use the Captivate audio editor to lower the volume or edit the audio. This also appears to cause audio problems when publishing. I do everything to the audio file outside of Captivate first. Now, when you're ready to publish, make sure your Captivate audio export is 98 kbps and 44.100 kHz (in other words that it matches exactly what your MP3 audio files are). So far, this has solved the problems of audio slowing down or repeating one audio file on multiple slides.

            I've also found that using WAV files in Captivate instead of MP3 files causes major problems. I know this is weird because when you import MP3 files into Captivate, they are converted to WAV files then converted back to MP3 when published. Go figure.

            It seems that no one at Adobe or any of the experts here on this Forum have ever run into this issue, since no one had even a suggestion for how to fix this. Odd. It happened everytime I used the Publish feature in Captivate 2 and now 3. It took me hours of trying variations of every possible encoder bit rate, file format, and sample rate to finally find some that didn't cause problems for Capitvate. The folks at Adobe need to spend some time in Captivate 4 making sure that the audio import and export functions are more idiot proof and can handle files without problems occuring. Not everyone is an audio wiz.

            Jim
            • 3. Re: Imported audio slows down or repeats
              Captiv8r Adobe Community Professional & MVP
              Hi Jim

              I think you hit the nail on the head here when you said: Not everyone is an audio wiz. I'm guessing this is a large reason why audio issues often go unanswered here.

              Another thing you mentioned was: I've also found that using WAV files in Captivate instead of MP3 files causes major problems. I know this is weird because when you import MP3 files into Captivate, they are converted to WAV files then converted back to MP3 when published. Go figure.

              While it may appear that is what's happening, I think it's misleading. Basically, when you import either format into Captivate, it gets converted to the other format. Point at a .WAV and you see a conversion occur as it gets converted to .MP3. Point at a .MP3 and it gets converted to a .WAV. The issue is that BOTH formats have to simultaneously exist inside the .CP file. But only the .MP3 format is actually used when you publish.

              While I would never purport to know all the intimate details of how the .CP file works, I've always assumed that the .WAV format was simply needed for the Captivate audio editor. This was somewhat confirmed when I once asked a Captivate developer if Captivate modified the .MP3 in any way if it was simply imported and used without modifying. I was told it simply "passes through". But I would temper that with the fact that we do have options governing audio. Not sure if those are used when publishing or only when recording within the application.

              Cheers... Rick