Hi Andrew - There are several hacked firmware files for this camera. Most that I have seen deal with allowing 3rd party battery usage, 17 minute video, unlimited video and variable shutter and aperture control during video recording. There may be others. I suggest you either (a) contact eBay and open a dispute resolution ticket to return the camera to get your money back or (b) try installing an authentic Nikon 3100 firmware from & as per instructions on the site:
https://support.nikonusa.com/app/answers/detail/a_id/18725
Understand that option (a) is preferential. If for some reason you can not do (a) then (b) would be the next step. Any time firmware is updated, there is a risk of damaging the hardware. This is especially true if power is removed during the process - but other things can happen, too. Finally, if (b) doesn't work for you then you may have to hack the firmware as shown in the link below (or your choice of hacks):
https://www.youtube.com/watch?v=ylQqH6Kfyno
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Published on Feb 16, 2014
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*THIS ALSO WORKS ON NIKON D5100*
Finally after 4 years we have a hacked/custom firmware that enable full manual video control on the Nikon D3100 DSLR. Just like the D3200 or Canon 5D, 7D ect. you can simple adjust the shutter speed/angle and the ISO sensitivity of video as well as the usual aperture control. You can even adjust shutter speed while recording!
Download Link:
http://simeonpilgrim.com/nikon-patch/...
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