Slow Narration in Flash

I’m a programming novice.  I’m trying to play narration in Flash, but the playback is slow.  I tested one of the narrations and it played 8.6% slower in Flash than the original file.  This makes my narrator’s voice sound plodding, like Lurch.  Is this to be expected or is there something I can do to prevent it.

I’m using Flash C4.  I’ve imported the audio files into the library and I’m using action script to program buttons to play the sounds.  I’ve actually programmed two types of button.  One plays a narration once.  The other causes narration to play every time a frame is reached.  This can be toggled on and off.

I’ve tried importing the files as wav and mp3.  I’ve tried different settings of the Sound Properties dialog box including different compressions (MP3, Speech, etc.), and different bit rates and qualities.  I also experimented with the publish settings.  Nothing has made any difference.  Any suggestions?