FiiO E10K Amplifier + Astro MixAmp?

I'm currently using Fidelio X1 Headphones with the Astro MixAmp.

The combination works great, but I want to upgrade once more and I'm wondering if anyone else has a similar setup.

I'm planning to go MixAmp > FiiO E10K > Fidelio X1.

If anyone here is using a MixAmp and a second amplifier, I have some questions:

Does the Dolby Digital signal work and not get altered/affected?

Are there hiss/audio quality issues?

I'm considering upgrading because the Astro MixAmp seems to have some issues balancing chat/game audio, apparently a Headphone amplifier can fix this. The chat is also apparently quiet if you want to use headphones.