A lot of times this has to do with the components being used. Like if a fully balanced device offers RCA inputs or outputs, and those are generated from the balanced signal being internally converted to single ended. Just to allow for more compatibility. That option often won't sound as good as sticking with the native balanced format. It is possible to handle that conversion well enough to be pretty transparent but a lot of designs cut corners here and it doesn't sound the same.
Not sure if this applies to your equipment or not. It could also just be that you prefer the Mogami cables to your other brand, even if they aren't as expensive.