You will see I have contributed to most of the threads on this subject. My position is that most of these problems are due to problems with the E-MU x64 drivers. I had none of them on this same hardware under XP.
The "scribble strip" issue is somewhat better in SONAR x86 on WIn7 x64, but all other issues affect both.
Bottom line is I think we are all going to have to give up on these interfaces, because E-MU has officially stopped supporting them, though the beta drivers for the 1616m are "should work".
I'm curious that you didn't mention the "silent outputs after rewind from record state" problem that I have with this interface under Win7 x64, but only with SONAR. Do you not experience this one?
EDIT: Just realized you are running the 1616m not 1820m, so maybe not all issues I experience are applicable.
I'll just add that I would not buy another E-MU interface even if it were guaranteed to resolve all these issues in Win7. The problem is I can't have any confidence it won't happen all over again with Win8. These products are too expensive not to be supported with driver updates for at least two O/S generations, unless it's not technologically feasible. I know of no other manufacturer who has left users so badly out in the cold with Win7 x64 (maybe Tascam?).