This is interesting. I run my Direct Stream DAC direct into a Musical Fidelity M6 power amplifier. For the last couple of years, I’ve generally used the “low” output setting, meaning that the volume control is usually set between 60 and 80, and there is no audible hiss from the speakers - even when no music is playing. This seems ideal. However, I have, at various times, tried the “high” setting - mostly because, with my Oppo Blu-ray player, even a volume setting of 106 can be insufficient.
In the past, I haven’t noticed any sound quality benefit from using the “high” setting, but, inspired by the original post, I’ve revisited this issue, and the “high” setting now seems much better than “low” - more dynamic, and, at the same time, smoother - particularly on vocals. Could this be related to Redcloud? Of course, the trade-off is that there is some background hiss - though not enough to be noticeable when music is playing. Also, the volume setting is now typically between 20 and 30 (except when the Oppo is playing).