Ok, this probably isn't possible, but you never know till you ask, right?
I've been nosing round here for a little while and found the wiring for the audio connector socket on the x51a. Stereo out, mono in (presumably mic-level, as opposed to line-level.)
But... is there any way, using that beast of a connector at the bottom of the device, to get, say, stereo line-level input? Maybe it needs a separate piece of hardware with it's own ADC - does anyone know if such a thing exists? M-Audio make a USB device -
http://www.m-audio.com/products/en_us/Transit-main.html - but I don't suppose it's possible to connect it to the Axim, is it?
I'm a musician and it would be great to be able to use the Axim to record while I'm out and about - it would then be a great replacement for the old Sony DAT machine I used to have.