Interesting. A similar experience.
I have been using a Geek Pulse DAC/headphone amp, but since it doesn't do MQA I plugged my Bryston analog headphone amp into the 818, and WOW the Bryston is much much better. But this was a level difference, too. Cranked up the Pulse and it was great too.


Music room: 818v3, DSP8000SE, Roon/Intel NUC, microRendu/LPS-1 into Geek Pulse Xfi into Audeze LCD-3
HT: G61R, HD621, MS600, Oppo, Avantgarde Solo
Library: MS600, Bel Canto, Mark & Daniel
Other: SonicOrbiter, GeekOut, Audeze EL-8