i am finally certain that i understand the problem, have fixed it and can resolve it if it reappears. after four months, you have to expect it's something simple.

the driver installation for the mixer has an error in it. the package needs to install two drivers: one basic driver (also used for asio) and a second driver on top of it (used for wdm). however, it was only installing the basic driver. so, i was getting various sound degradation and inconsistency due to the system using the wrong driver.

i was actually about to give up on the kmixer for the device. i wanted to verify i was getting a good sound out of asio, so i disabled wdm in the mixer and tested through cubase. it sounded right. out of curiosity, i re-enabled the wdm with the asio running and the secondary driver installed. it has since passed all stability testing; the issue seems to be resolved.

i have a higher confidence in stating i'm done, now, because i feel i understand it. i have some more listening to do tonight. i need to edit and upload a vlog from the last three days. i also need to eat. and, tomorrow i need to do laundry and test one more time. but, i'm confident i'll be back at this within 24 hours, and could even get some new mixes up by saturday.

i didn't notice this previously because the wdm installed disabled and i had to manually turn it on. i don't know why that behaviour changed.