Could I suggest that, instead of starting with the assumption that cables make no difference to sound quality, you actually listen to different cables connected to the R1 (to which I assume you have access, since you mention that you've opened it up)? Use a quality speaker cable to connect the R1 to your amplifier (which one is it, I assume it's a quality make?). Then try 14 gauge OFC zip cord to connect the amplifier to the R1. Please report back on the result. I might take your comment seriously if you had actually tried this, instead of spouting some theoretical spiel without actually testing your hypothesis.
The scientific method consists of observing (in this case listening), then trying to figure out why what is observed is happening (for example, why the change of speaker cable results in a change of sound quality). The non scientific approach (let's be frank, it's called prejudice) starts with an untested assumption, spreading this untested assumption via social media, and refusing to actually testing the assumption (because that might be embarrassing, wouldn't it?).
Please put your money where your mouth is, and actually compare a quality speaker cable with 14 gauge OFC zip cord to connect the R1 with the power amplifier.
I'm waiting with bated breath for the results of your experiment.