Muso almost there

My Muso problems have subsided with the new Samsung which has an optical out which works with the Muso and the firmware update which brings Spotify Connect back.  Everything is sounding great and we have very much enjoyed "Muscle Shoals" and "20 Feet from Stardom on Netflix".

My last issue is the variability of the audio feed from source to source.   The audio volume is fixed from the TV to the Muso because of the optical.    But every source has a different level.   Individual cable channels, Netflix, Youtube, all have a different volume.   Is there any way to fix this issue?