It's telling you the last thing you where using as an interface isn't there anymore. What ports is it saying arn't connected. You need to go into device setup in cubase and select the Alesis. Check the top thread if you don't know how.
Is there an option on your pedal that lets you select between amp/DI. I know with my Line 6 pedal it sounds like ass if I have it in the wrong mode.
oh yeah, nothing wrong with Line 6 stuff.
Option B FTW.
I don't know where you heard about the latencey issue but it's BS. Any interface with it's own ASIO driver should perform at least as good as the x-Fi.
Like Gecko said it's probably a user issue. Any unit I've ever used always has enough jam to blow your head off. I'm getting old though so maybe my definition of loud and yours don't match.
Check the specs on your keyboard, if it has balanced out you should use a balanced cable (TRS), that can fix all sorts of interference. Could just be a bad cable too. Try switching cables if you have another even if it's only TS.