For music playback, you can achieve this by going to settings, room settings and then chosing the room your 5.0 setup is in. From there, go to advanced audio, surround settings. Click the button behind "music playback" to change the setting from. "ambient" to "full".
For TV audio that is in stereo, see my reply
in this thread. If the TV audio is in stereo, Sonos will upmix it to simulated 5.1, there is no way you can change it to output full stereo on the surrounds.
Thanks Sjoop1985, is the actual configuration I have. Also I check the thread. So, nothing more to do. Regards