No, synced is a timing thing. All GOUT-synced audio will work with any GOUT-synced video, so people’s lips match up with the words coming out of their mouths, etc. Silver Screen isn’t GOUT-synced, so you are a little more limited in your audio options (or you add dark frames for the missing video to make it GOUT-synced, either way).
Version 1.6 of the SSE is gout-synced though!