I am not an Ableton user but I have had similar issues with the Quantum 2626 and Studio One. Studio One has two layers of buffer processing with the latter called dropout protection. Increasing this and using the green Z feature the Quantum has inside Studio One does achieve smaller buffer sizes than when drop out protection is set to minimum rather than maximum. If Ableton has a similar feature I am unsure.
I have been trying to swap out thunderbolt 3 cables. I have used two different two meter cables that allegedly support 40gbps. I have not discerned any difference but I think there may be a possibility that a cable longer than 1 meter may not support 40gbps (despite a seller saying otherwise).
Before I got the quantum I was on Firestudio Project and I beleive buffers at 128/256 resulted in longer ms latency than what is achievable with the Quantum.
When Quantum is used inside studio one, It performs better (without so many pops/clicks) when the monitor button is unselected on track inside studio one.
I don’t know what interface he is using in the youtube video but it shows the impact of monitoring a track on pops and clicks.
The footnote* of <1ms latency with 64 buffer on Quantum at 192 Khz on 2016 Mac with an i7 is probably one single tracking session of a guitar or mic.
