Is well known two applications can not access the same video source, at least in Windows, but, for example, multiple flash players can do it running in the same browser.
Would be really great Flash Media Live Encoder running multiple instances be able to use the same video source.
Sometimes we need the same video source to be taken with different audios (translations) and we need to use a software video splitter or two video capture cards, would be easier if Flash Media Live encoder could do it natively
Osprey capture cards ship with their Simulstream software package that allows multiple programs to access the audio/video input. As far as I know their isn't any limit except for the limitations of your hardware. We use an older Osprey capture card to capture an analog signal and then our streaming service requires that we have a separate instance of FMLE running for each unique bitrate that we are streaming. So typically we run five (5) instances of FMLE and we've run as many as eight (8) instances without any problems.