I feel your pain and resulted in me starting this topic.
I still have problems once a month. (Did I really say that?)
Anyway when turning on does not result in the "usual" of it working, I find that the key is, even when the sMS appears to see the dac correctly, the "fix" is to make sure the dac is switched off when the sMS is turned back on, make sure that it sees no dac connected, then turn on the dac and then check that it is recognised by the sMS and then everything seems to work. A real pain in the arse, but not as much as making sure the stylus is clean (every 20 to 30 mins, rather than every month) between each record change. :-)