Replace Ayre Codex with Topping D90 DAC

I’m in the “any distortion is just noise” camp. For DAC chips, I tend to favor AKM for their VelvetSound profile (no ESS distortion hump) and the AK4499 truly is an excellent implantation. It’s AKMs first current drive chip and it’s a huge step up. It’s also a pain to implement into a functional DAC. They really nailed it with this chip. 

Hopefully you can figure out what's going on with your codex but if you need a new DAC the D90 is an incredible bargain.  I know it seems to rankle some feathers that something that costs $700 can deliver but if you want transparency in a DAC it's hard to better the D90. That's my 2 cents and yes I've heard it and looked at the measurements. 

Topping good? Really? Don’t believe it. No way better than the codex. 

Ayre Codex is way better than a Topping. Whoever tells you Topping is great, either (1) never tried anything other than a Topping, or a similar chi-fi DAC, or (2) believes all DACs sound the same, bits are bits, etc.

You might want to consider Schitt's Bifrost 2 Multibit. Same price as the D90 but fully user upgradable, both in firmware and software. DAC obsolescence is almost guaranteed given the pace of development in DACs. It is generally acknowledged that the D90 measures exceptionally well but the BF2 has a better sound. Let your ears (and only your ears) be the judge of course but for me, upgradability is important in DACs.

J.Cip