I have this same problem. Ever since Avast upgraded itself to the 2014 it breaks all streaming video. That includes YouTube, Lynda.com, etc. Also it breaks loading images over 400 or 500k. Only solution I found was to completely unistall Avast. Re-installing Avast brings back the same problem.
Since we don't know the problem experienced by the original user, how can you have the same problem
Details are still lacking. We can't answer questions without knowing the problem. What error messages are you getting
Where are you located, what kind of a system do you have
what other security programs are you running
I have no problems viewing or producing and sharing videos and pictures of all sizes.