[swfmill] preparing an mp3 for conversion using ffmpeg

[Ryan van Roode]

Hello,

Has anyone managed to use ffmpeg to prepare an mp3 for conversion to
swf sound object using swfmill? In the past I have used lame to
prepare the mp3 like this:

   lame --b 48 --resample 44.1 sound.wav lame.mp3

I am trying to accomplish the same thing using ffmpeg with this command:

   ffmpeg -ab 48k -ar 44100 -i sound.wav ffmpeg.mp3

When I try to use swfmill to convert the mp3 to an swf sound object, I
get this error:

   WARNING: this file is not a valid MP3 ffmpeg.mp3
   xmlXPathCompiledEval: evaluation failed

Thanks in advance for any help and I'm sorry if my question falls
outside the scope of this list.

~ryan