I got mine and finally had a chance to test it a bit tonight. I set it to LINE IN/COMPONENT and connected my 12V battery box and an external stereo mic. In this configuration (with the mic and batt box connected), I could not adjust the input level AT ALL. The little number in the lower right-hand corner does not appear at all. I got the same result when set to LINE IN/PORTABLE.
However, when the mic/batt box is completely disconnected, the little input level number reappears, presumably because the unit has automatically defaulted back to its internal mics.
This is most confounding device I've ever seen. Why on earth would the input level control be intentionally disabled when recording from an external source?!?! For what conceivable reason would they add this "feature"?
I realize that you could use an external pre to adjust your gain, but that defeats the entire purpose of this unit (i.e. its small size). Why bother with a micro sized recorder if you have to carry around bulky preamp with it? Besides, I typically record VERY loud shows, so I don't need a preamp at all.
It's a real shame because this could have been the ultimate stealth recorder. The unit is so small (smaller than a stack of three credit cards). It also appears to be well made, and the internal hardware is probably quite good. I wish there were a firmware update available, but there isn't (I checked).
Perhaps I'll call Sanyo to ask if I'm missing something.