Hello
I have been experiancing the following problem -> alls .flv .mp4 and .avi it plays as audio while there should be a movie
You need to buy the codec license from the raspberry pi people first. I had the same issue
mp4 and avi should NOT need a license - not sure of flv, but unlikely. Check the codec information for the files and post here.
Check with the "O" key whilst playing. mpeg4 or similar will need a license.
flv, avi, mp4..etc are just containers, the actual compression technology is what counts. In other words it may be a license issue.
What codec is being used?