I thought the problem might be due to :private window setting, though i can't see how to open a non private window or if that is the problem. I am a subscriber to Curzon Cinemas ( UK ) and it has worked in the past in Safari and Firefox, it is ok on my Ipad, and have whitelisted the Domains on my addons but still no joy. I am using a 24 inch early 2009 Imac which i believe is now unsupported ,but it works well enough in all other respects. Could it be a problem with the Private window ? I don't see why it should, ore like a blocker but as i said tried to deal with that and can't see anything in my settings which would restrict playback, the only thing i have not tried is restarting with all addons/exten's disabled.