BTW, with that said, usually the cost to manufacture a DAC is very low. AK4493 is around $5 each. xu208 costs $7.5. Various analog components (OPA1612, OPA2140 op-amp) are all sub $5. AK4118 bluetooth receiver is around $2.
PCM5102A is half the price of AK4493, and cost around $2. so if you compare MX3 and DX3, their raw material costs don't differ too much. The actual component price makes up very little in the total device price.
Another example. ES9038Pro is roughly $74. ES9038Q2M is $13.8. Dual ES9038Q2M costs $27, so less than $50 difference. But usually ES9038Pro devices have much higher price than ES9038Q2M devices (for instance, compare $1300 SMSL VMV D1 and $250 dual chip SMSL SU-8), whereas other costs (power, firmware/driver dev, pcb, etc) are almost the same.
So I would say DX3 is 2x the price of MX3 is solely because premium grade devices sell for a premium price. That's where the profits come from.
Today's DAC chips are so good that even PCM5102A is way beyond human hearing range, and why it's chosen for Objective DAC. But people want better spec products. That's why there's premium grade products selling for 5x-10x the price