Surround sound not working w. Sony TV

It probably is working properly. If the audio source you are feeding it is not in surround format (specifically DD5.1) then there is nothing for the surround speakers to play. If you are playing a source you know to be in DD5.1 and you are not getting surround sound, THEN you have an issue.

As far as I know, YouTube only does stereo, so as John suggests, you wouldn't get any sound out of the surrounds.

As for HBO-go, you should be able to go into the audio settings of the app, and make sure it's sending a Dolby Digital signal. Worth double checking the audio settings on your TV as well, while watching a movie that is in Dolby Digital, to make sure all of the options there are set to Dolby Digital, and any extra things (additional surround features, etc) are turned off. You want as close to direct pass through as possible, the more that you allow Sony to alter the sound, the more delay you're going to end up with, and be unhappy about.

In fact, any and all devices that you have connected to your TV via HDMI should have their audio settings checked and moved to Dolby Digital (and not Dolby Digital Plus, or DTS, or any other format), where possible.

How do you get surround sound from Spotify?? It only supports stereo. Can you share an example of something that does surround on Spotify?