My MPC X is also broken.
The whole control surface board is out which means no oled displays, no response from any buttons. The MPC itself works, it boots as normal, the touchscreen works and it flashes the pad LEDs on startup but no control surface.
I called InMusic / Akai pro support. I spoke to a nice guy there back in March. I was having intermittent freezes and hiccups in standalone mode but generally fine operation in controller mode. My X is well out of warranty, too far to go down that route. I'm also an engineer with a fully tooled workbench and the ability to do most of the repairs they'd likely do in their service centre.
What I dont have is any service information, schematics or access to knowledge bases to help isolate the problem. The chap I spoke to in March was very helpful and said I could work on it over the phone while in comms with one of their techs. I'd obviously have to pay their hourly rate but I'd simply carry out the tests and procedures they'd do but on my workbench. Their tech knowing the equipment would be able to fairly quickly isolate the core of the problem. I was frankly surprised by their willingness to help me on this level and left me with very positive impression of InMusic/Akai. But my workbench wasn't setup back in march so I didn't follow up immediately with him.
So I've made do with controller mode since march and then last week I found it totally out of action. Called the same UK support number but this time I didn't get the nice guy, rather an irate lady who clearly had no understanding of the deeper technical details and absolutely no interest in helping me. She said she was the supervisor and absolutely refused any possibility of my working with their techs over the phone stating this is absolutely against their policy.. That whoever offered to help me in March was acting against company policy, essentially she almost implied I must be making it up,,,
Her attitude is of course what I expected in the first place.
So what she wants is what all these big greedy companies want. They want me to do is send it to them so they can tell me oh your MPC needs a £700 circuit board. Not an option, I'll sooner scrap it for parts,,
Now in reality I suspect my machine just needs all its ribbon cables reseated, maybe replaced but all I think it needs is to be fully factory reset
The key thing to note is:
On opening the setting info / about page it says my X has lost it's serial number and under control surface it says unknown. So there is clearly a break in comms / machine amnesia. The whole thing just needs a hard reset, both sides of the machine, that is CPU board and the Control surface.
I'm an engineer with a workbench so I've explored all the main test points and all the right voltages are in all the right places. I think its just a case of amnesia.
So does anyone here know of any reset procedure. I tried connecting it by usb but the MPC app doesn't see it nor does the MPC register there is a Mac on the USB bus.
Any guidance / suggestions appreciated
it's only works with the external ones but ( hooked up to xone 96 USB 1 ) it's popping out latency " pops " I hear trough the studio speakers it's weird cause the laptops don't when connected to the same USB - B port , I have the unit buggy since I've bought it from another person with warranty and the bill... but now the thing is totally unusable in standalone mode... Should I do or ask something / from / towards Akai Or something else ? Cause this an costly unit laying bricked aside... Sad story... 
Hoping something neat ( dreaming )
