Jog-wheels: Depending on the way that VDJ handles the inputs on record positioning and so on, I think the best solution would just be a simple rotary encoder - even a detented one (one with "click-stops") could be used, as I'm told it is a relatively simple matter to convert them to non-detented operation. Power/shielding concerns: Every midibox ever built is powered off DC. AC current will introduce interference, but the general concensus is that DC will not, even in the same cable - look at Wisefire's Midibox Axe thread (http://www.midibox.org/forum/index.php?topic=6431.0) for more info. The only thing I can think of with the 2.56" spacing as you call it is to space out everything such as buttons and LEDs in multiples of 2.54mm, since veroboard (vectorboard, prototyping board, stripboard) is set out with holes 2.54mm apart (The reason it's such a strange number as 2.54 is because it's 0.1 of an inch). If you're mounting your frontpanel switches and LEDs on veroboard, then you're in for a headache if you don't space them that way. Oh yeah, tact switch covers: I've not really found too many great ones, but they are out there. Hopefully someone will reply to this thread with where they can be found, so I can get some of the damn things as well :P /Edit: Added URL for midibox axe