You can't. That's the way the audio is being sent by the provider. The Roku isn't doing it. Now there might be an audio setting on your Roku to help, but not every player has it. If you press the * button during playback, there should be some options appear on screen. Look in the audio options and see if TruVolume is available. If not, see if there's some other audio setting that might do something similar. Different players have different functionalities. But do note that using any of these audio settings will drop your audio to two channel stereo. You can't use those audio settings and retain 5.1 audio.
Dan
Roku Stick (3600), Ultra (4640), Ultra (4670), Premiere (3920), Insignia 720p Roku TV, Sharp 4K Roku TV, Nvidia Shield, Windows 10 Pro x64 running Serviio and Plex on a wired Gigabit network.
