Hi,
I agree with other comments. I suspect that you have a faulty Node. I bought mine a year ago with the sole purpose of streaming Radio Paradise MQA. Used as a stand alone until buying a TEAC ud701N which accepts MQA in via spdif and usb. Having read your findings I had a session today with the Node as a stand alone player/DAC, listening to RP and quobuz hires tracks. Bass is solid with good definition of bass guitar and kick drum. Not quite as good as the TEAC nor is the wide detailed top end. I don’t hear what you describe. Amp is Luxman and speakers Dali Epicon 6 with hybrid soft dome and ribbon tweeters. Reasonably resolving. Mazzy Star is playing as I write and lovely “air” to vocals and instruments. Hope you solve the mystery. Both TEAC and node are fed with Audioquest cinnamom ethernet cat 7. Audioquest power cables and Chord rca/ XLR./ coax.