Advice for headphone amp and dac

Not to be rude but your headphones are no where near good enough to justify spending $700.00 on an amp/DAC..I have also owned Schiit gear & I myself was NOT impressed,finding the Hybrid Vali II amp highly microphonic..
With your budget I would get a new pair of HiFiMan Sundara & a Xduoo TA-22 Hybrid amp/Dac or even a pair of HiFiMan Ananda Nano & a budget amp/Dac from Topping,SMSL or Xduoo...

My system is low cost and top system if i think about the AKG K340 experience after his 6 steps optimization ... ( it was the only one real hybrid ever designed and the best headphone flagship of AKG because of his complex acoustic design put to rest because of optimization cost and the other possible headphones design experience in the more portable emerging market window at the times )

For the speakers: very good small nearfield system with the sextett as complement...

All the gear cost of my 2 system is : 1000 bucks....

My main system:

Hidizs AP80 pro battery powered and files bank /dac/equalizer---> Sansui Au-Alpha 607i ---> hybrid headphone AKG k340 (bass version)+improved mods... Nothing else is necessary -

my very satisfying secondary system :

And SPS nos french battery dac+tube preamp Douk P2+Fosi mk01 amp+ AKGK240 sextett or M-Audio AV40 speakers modified

I dont need to upgrade ( i even tried ) ...

Happiness in audio result from acoustic information and experiments not from buying gear...

It is my experience...

Buying gear is often the easy way to reach results but the lost occasion to study,learn and experiments to reach the same goal at a very low price...

Chord Electronics Mojo 2 (headphone amp and FPGA DAC) Fits your budget well.

Powerful enough to drive almost all headphones (not electrostatics)

At its price point it is class leading. Excellent clarity, detail and separation and will plug directly in to your MacBook.

The Mojo will also scale well as you invest up the ladder.

Enjoy the music!

I bought a Topping DX3+ for headphones and it’s not bad at all. $200 from Amazon. You can go up the Topping range if you want to spend more money. 

Mojo2 will do perfectly. I suggest avoiding the Poly streamer. It’s a nightmare losing connection and needed to be reconfigured often if used with a phone. Less problems with computers. Mojo2 has also an excellent EQ.