I've been mucking around most of the day on this.
I'm still inclined to say CK4+ performs best on internal memory here, I cannot get the same sound quality using microsd it seems, close, very close but no disco. Whether it's a power drawing issue when using the external card slot, bug in the firmware, hardware, or a faulty unit I don't know. I just can't make it sound exactly the same. This is something I don't think everyone will hear and maybe I'm nit picking, though to my ears I can clearly hear the internal memory sounds more dynamic, more power, better refined across the board. The bass problems I constantly mentioned improve, separation and soundstage depth. All these little areas contribute making one fantastic listening session.
You know what? I don't think there is a fix, I think only the designers of CK4+ would know what's going on. Maybe they thought it would slip through and no-one would notice because the amounts I'm talking about here in difference are rather small, I'm sure this may go unnoticed by many people.
To sum up, I think it's just the way the player is personally... I shall continue using CK4+ from 8GB internal as a glory player for now. Because it's sounds so so so good running from internal memory.
Edited by H20Fidelity - 12/8/12 at 2:40am