Does anyone know a solution to this problem?
I have exactly the same issue, I have checked the file using GSpot and I definitely have all the codes installed but for some reason the file when converted from mpg to flv contains no sounds. I have also tried using different file extensions but this does not seem to have any affect.
I know there was a request to post this in the Professional Forum, if you could point me in theat direction it would be appreciated, there isn't a forum specifically for the Adobe MEdia Encoder software.
I have had good results creating FLV's and SWF's using the freeware Super encoder from www.erightsoft.com/SUPER.html. It is kind of difficult to find the actual Super download link amidst all the ads on the page that also try to get you to download other (not free) software. What you are looking for is a paragraph of blue text that begins with the link " Start Downloading SUPER © " then on the page that takes you to a link in a paragraph of red text that says "download and use" which finally takes you to a page with a link that says Download SUPER © setup file from our dedicated server which is where you actually download the software. Once you download it, it does seem to be spyware free and works pretty well for transcoding among all sorts of different file types. Hope that helps.
This is not about the Adobe Video Encoder. It's an issue of the source mpeg file which has 'muxed' (muliplexed) audio and video streams.
QuickTime is capable of playing those, but not able to export separate 'demuxed' audio and video streams.
Neverhteless, there are free tools, quite popular, which are able to deal with mpeg2 and convert them to FLV:
AviDemux (avidemux.berlios.de) — "...a free video editor designed for simple cutting, filtering and encoding tasks.
It supports many file types, including AVI, DVD compatible MPEG files, MP4 and ASF, using a variety of codecs.
Tasks can be automated using projects, job queue and powerful scripting capabilities.
Avidemux is available for Linux, BSD, Mac OS X and Microsoft Windows under the GNU GPL license."
Another one is StreamClip by Squared 5 (squared5.com) — "...a powerful free video converter, player, editor for Mac and Windows. It can play many movie files, not only MPEGs; it can convert MPEG files between muxed/demuxed formats for authoring; it can encode movies to many formats, including iPod; it can cut, trim and join movies. MPEG Streamclip can also download videos from YouTube and Google by entering the page URL."
I faced exactly the same problem and Google'd to this post. No other similar posts on Adobe forums had any solutions.
Thought this might save you some time for doing a better video!