Connector break-out and i/o specs anyone?

I am looking at the possibility of making a connector break-out for my D5200. It should be possible to make something that can be attached to a camera cage so that there is no stress on the connectors of the camera. And at the same time allow for better plugs.
One thing the camera do not have is a headset output. Does anyone know if the audio on the AV output is active during recording of video? This could then be a good reason to make a headphone plug on the break-out. Using standard size HDMI would also be good. As well as figuring out something to allow connecting a couple of XLR's to the audio input.
Does anyone have the complete spec for the audio/mic input? I got an XLR to mini-jack made, but getting an incredible amount of noise/hiss on the recordings to the point where the audio is completely unuseable... I would be happy to be able to connect even one handheld mic...
Any info you might have one the in and out of this camera is appreciated!
(Yes - I am going to buy an adapter/recorder eventually, but it might take a little while to save up... Any electronics are expensive here in Brazil...
One thing the camera do not have is a headset output. Does anyone know if the audio on the AV output is active during recording of video? This could then be a good reason to make a headphone plug on the break-out. Using standard size HDMI would also be good. As well as figuring out something to allow connecting a couple of XLR's to the audio input.
Does anyone have the complete spec for the audio/mic input? I got an XLR to mini-jack made, but getting an incredible amount of noise/hiss on the recordings to the point where the audio is completely unuseable... I would be happy to be able to connect even one handheld mic...
Any info you might have one the in and out of this camera is appreciated!
(Yes - I am going to buy an adapter/recorder eventually, but it might take a little while to save up... Any electronics are expensive here in Brazil...