I have an older Roku 3 and a (2nd gen?) Amazon FireTV box (the flat box thing not the stick), and the sound from the FireTV box is far far superior than that of

I have an older Roku 3 and a (2nd gen?) Amazon FireTV box (the flat box thing not the stick), and the sound from the FireTV box is far far superior than that of the Roku 3 (did a test using the same soundbar). Not sure if Roku has improved on its sound output since then or not (the Roku 3 I have is of course pretty old).