Computer Help and Support

FLA is a Flash - Video Container. SWF can be looked at as an application. One of the features of the application is to display audio and video from a contained file.

Rather than "converting" to FLV, you may want to look at something like a SWF Extractor. An extractor can rip-out the contained video and audio (usually MP3 for audio and MP4 for Audio/Video) and write it to a file. Then that file format can be converted, or placed directly into an FLV container.

Most of the so called "SWF to Video Converters" are to capture the animations created in an SWF file.. like some of those interactive games and ads that move sprites around over a timeline, by way of Flash and ActionScript. If all you want to do is play a video file, look for a ripper/extractor.

Hope this helps.