Thanks for that. I fear I am the bearer of bad news. :|
The Neon TP3730F is a re-branded Daewoo panel, with a Xuguang Tech main board. Commissioned by Cello electronics for sale in outlets such as Morrisions, Aldi etc. The Neon brand would seem to have been discontinued. None of that is really vastly important.
After a bit of google-fu it would appear that any of the models with a xxxx30x are 720p or so termed "HD ready" the xxxx70x models are 1080. Some 1080i some 1080p.
A depreciated amazon listing
here clearly lists that model, a Neon TP3730F as "HD ready" therefore only running a resolution of 1280x720, or 720p. I'll come back to this in a moment.
I had the same problem. A few other sites claiming to have a manual but demanding either a "free registration" or "download our software to view". Meh. IDBY
I concur that I believe this is what's happening.
Until I saw this. [uhh]
Which got me curious for a little more google-fu.
I think your panel is an attempting to display 1080 or "Full HD" on a 1366x768 rated panel. Hence the under scan. The 1366x768 resolution also gives a ratio of 16:9. The image clipping you are seeing is the difference between the two resolutions.
My maths is terrible but, if the xbox is outputting at 1080 lines and your TV is displaying 768 lines, that leaves a difference of 312 lines. Divide that by two in order to split the difference between the top and lower edges of the screen, which gives 156 lines, which is the clipping of the image which you are seeing. It is also missing from the top of the screen but no where near as noticeable. When this element is factored in to the mix it makes sense. OR, it is only clipping the lower edge of the display at the full 312 lines. Hard to tell from here. Largely dependant on how the control board is interpreting the signal either from 0,0 (top left of the screen) or the centre point of the panel.
A bit of a cheap trick my the manufacturer to enable to display of "Full HD" on a slightly over "HD Ready" rated panel. This is not helpful when running something like an xbox one into it. Humph. But when it was retailed the xbox one didn't exist.
In the display setting of the xbox one there is an auto detect setting, which I'm sure you are more than aware of. This resolution mismatch may possibly be enough to fool the xbox when probing its primary output as over 720, therefore deciding it must be a 1080, when in fact it is not. If that makes sense.
The lack of any image fine tuning controls on the TV only further exaggerate matters. If you were able to tweak the display image then that may help resolve the issue.
Short of a straight TV upgrade, i'm not sure it can be fixed even with any kind of inline up-scaling device (like an AV receiver for example) the issue will persist as it is the primary output device. The only other thing I can suggest as a budget remedy is somewhere like CEX or similar trade in place, with a second hand PC monitor with an HDMI input.
I hope this helps.