For me, I got noticeable improvement when switched from Directsound to ASIO / KSP but many don`t make difference. I prefer ASIO because it seems somehow tinybit more dynamical and "sweeter". Maybe it`s pseudo but whatever, I prefer it over others. KSP was "crisp & dry" sounding to me compared to ASIO. Aslo,
haven`t had any errors under W7x64.
Thanks CoiL, like i mentioned, will not immediately jump into switching between modes of audio output.
will wait for a long while for the tubes to be burnt-in with regular use and then slowly switch. I am already seeing some (slight) improvement in some music which i used to hear and now hearing through AUNE.