Indeed, my bad - its PCM1794 instead of CS4398.

Although personally usually I can't identify chips by sound differences nor tell if the difference is in the chip or implementation of it. The Z is the first time since I've stopped using X-Fi where everything sounds properly, flat/no issues with tonality. I did look for ZxR prior, but it is a hard find, and I just came across Z for $39 from a friend. I do like it to the point Ive stopped feeling like I need to upgrade/buy something further... and I do feel like I wasted time and money with all those external solutions.