Originally Posted by Tempest

Forgot to mention that converting to flv requires multiples of 2.. so it won't like 300x235... you'll need to do it as 300x234 or 300x236.. sorry about that.. I ran into the same thing once and I forgot about that.

Once you convert using ffmpeg, you then need to also use a tool like flvtools2 or flvmdi to fix up the flv with metadata and then your problem will go away...

Even when you convert files to flv using videocharge etc., you should still run flvmdi on the files.. On your server you would use flvtools2.. not sure if there are alternatives.