Sorry, I'm not.
All four X-Fi opamps are powered from +/-5V. All their pins 8 and 4 and connected to the output of 7805 and 7905 regulators. On the end of the line, there is additional cap on the +5V line.
Probably/likely for the MC33078.
Pin 8 of the MC33078 is connected to the +5V line, as other opamps are. Pin 4 is ground, tough...
When pin 4 is ground, it can only be, that the opamp is giving +5V only.
Sorry, this is very simple measuring and I did it twice to be sure. I cannot be wrong on this one.
I did not check that "on the fly", but if the pin 4 on ground get somewhat flipped when MIC is enabled by some transistor to the -5V, then it has to be connected to the transistor and not to the ground with zero resistance... Hence even on the fly things can't differ from my findings that the MC33078 is powered by +5V only. Weird, out of specs... but Creative is simply sometimes being too creative.
Regardless, LM4562 sounds as interesting alternative, but it is a known picky opamp that likes to pick RFI a lot... so I'm somewhat not happy from the idea...
I rather push on the AD8599 and try it there. Why? Because in THIS thread:
http://www.head-fi.org/forums/f6/sta...9/#post3536731
Is the AD8599 (among ohers) run from 3.7V lithium batteries and it works. His specs might be kinda different from what the datasheet says, tough the LM4562 sound too harsh/sharp to me... maybe is the AD8599 still better choice even at +5V only?