Did you install the Hi Def NES yourself or have a professional like Wes Almond of retrofixes.com (my go to guy for console modding) or Voultar (GameTechUS's recommended installer) install it for you?
If you installed it yourself maybe you made some sort of mistake that led to a short over time leading to your current Everdrive problems? (which then obviously wouldn't be Everdrive problems technically but that of a messed up Hi Def Nes install).
Or maybe surprisingly enough you just need to try a different SD card brand altogether?
And yes I know how ridiculous that last one sounds but for whatever reason I have found out personally through trial and error this is usually what ends up fixing 99.9% of ALL Everdrive related problems.
For example I have the best version of the Sega Genesis Everdrive and I had everything all set up and working perfectly but packed the Genesis away for several months and when I went to boot things up again the Everdrive no longer worked despite my various attempts to format and fix things and even put the latest OS on it, etc.
What finally DID end up fixing things for me was trying out a different card altogether and now it works like a charm again with the latest OS and everything.
So krikzz products can be a little bit finicky and weird at times but usually just trying a different SD card solves the problem.
I actually sent in an Everdrive 64 to krikzz engineer before as when I got it and tried things out on the SD card I had ready for it, it just gave me an error code.
The engineer sent it back to me without telling me what to do or if anything was wrong and I was pretty pissed trying to get it to work again and still getting the same error code.
Well somehow I had the bright idea finally to test out a different SD card and that totally solved the problem and where I finally figured out that this is typically the way to fix Krikzz's products.
I wouldn't be surprised if you even have to try a few different brands before getting things to work again.
Anyway if I knew this whole different SD card thing sooner it would've saved me about a month or two without my Everdrive 64.
