Solo streamer

I haven’t heard the OP DAC but had some time with an earlier Benchmark DAC that I thought was fantastically detailed but bright, especially with my B&W 803D speakers.  Perhaps the upgraded streamer is bringing some of that out.

  It might be worth trying DACs from a different manufacturer but perhaps in the same price range as his current DAC

The brightness is an issue only very occasionally. I definitely don’t think it warrants a new DAC. Most of the time the balance is excellent. I’m replacing the stock USB cable with the Shunyata Gamma USB cable to remedy any remaining issues.

I owned an Aurlic Aries G2 and now several Aurrender. The Aurlic was glitchy in operation and its sound quality at its price point was not up to Aurrender’s lineup. I am constantly surprised at how good Aurrender are and they continue to improve. I have read that the new Aurlic Aries G2.2 has significantly improved sound quality, but I have not heard one. 

RV, FWIW, but as I recall, you have a Schiit Loki. A lot of 'brightness' folks seem to complain originates in the upper-mid frequencies, i.e. 1500 to 3000 hz. Mostly on sources. Your complaint seems to be (logically anyway) coming from your sources and/or the recordings).  I think your CJ may have a tape loop. If so I'd suggest that you put the Loki in the loop and when you encounter that brightness flip on the loop switch and fiddle with the 2K knob some and see if the brightness goes away. You could put the Loki between your source and preamp but that is something I'd not  do if I really loved your source. Maybe a better solution, and a lot cheaper anyway, than by shopping other sources or wires which might just bring you different problems. Good luck.

@newbee

Thanks for your suggestion and your good wishes.
I had actually forgotten about the Loki. You have a good memory. It was removed years ago because It didn’t get much use at all.
I spoke of the brightness when the Aurender was first installed. I can’t remember it happening lately at all.   The Shunyata cable should enhance the sound even more, I hope.