Try it extensively and let's see what happens. Looks like residual of the previous update.
P.S. Update your location please.
So, my last tests on the MV-1C were OK, all in all, as far as game functionality is concerned.
Flashing the games seems OK, no white graphical garbage at least. I now flashed the games Blazing Star, Magical Drop II
and Metal Slug 3.
- Blazing Star (slot 1) has some graphical glitches in the intro. There seem to be one line of pixel jam at the top area of the screen...
https://drive.google.com/open?id=1YKRrvMFh9WNdIUz7Kgh-zfzC2a4InlnS
- the other two games seem to work flawlessly
Don't know if this is normal!?: I am able to reset the menu ONCE with the select button...
https://drive.google.com/open?id=11WmK1AOIvEqO-keECWizYIL_Bb5vf04e
UPDATE: I emptied all slots and changed my game setup to: (1) Blazing Star, (2) Metal Slug 3, (3) KOF 2003
it ended up with this freeze screen
After switching off and on again, the menu showed all the 3 games in its slots.
I didn'T start any of those, emptied the slots an flashed again in a different order.
It worked, the procedure looked like this:
https://drive.google.com/open?id=1W8zcqLR_NOsXDqNfvNZGIz9fogBU0mHD
EDIT 2018-08-03:
Here is another video
https://drive.google.com/open?id=1dlYZE5Wam-yR7ymiplhk4hhj6CI5KGdp
In the first two parts you can see the white pixels while flashing. There's few of them but I had loads last time, when the Multi was running for some time.
The third part is showing that the buttons in AES mode won't work with Metal Slug 3 - when I set it to arcade mode, it works...