My case using driver v21 with 82579 inside Windows 10 1607 redstone x64 without any problems, sound more steadier than windows 8.1 especially much more clearer bass. So I guess Windows 10 had redesigned a much more stabler multimedia clock.
I'd just had a look on MMCSS of Windows 10 and found that, now no more MMCSS service inside the services list, but found an mmcss.sys driver inside the driver folder, so I guess the MS had moved the MMCSS from a common service and become a subsystem driver module loaded by the caller software, and stay inside the software process.
And so if you still have that problem of dropouts, have you ever tried to report that to the Feedback Hub inside Windows 10 to MS, other than reporting to Intel?