Most media players allow you to apply ReplayGain: ReplayGain - Wikipedia If you make random playlist, use track gain. As Nicoff pointed out, it is digital volume control. This won't do any harm.
Love my mfsl Dire Straits CD collection, The latest versions sound really good :celebrate008_2:
I started out with AQ (Speaker +Interconnect) moved up through the brand over time. Eventually landing on Oak (Speaker) + Earth (Interconnects) Full loom. I'm not a fan of mixing and matching...
What are your reference cables.