I have a magnasonic DVD849-2

light on battery (facing the back, neer the bottom) is flashing when charging and constant-on when charged.

If there isin't a light flashing when the adapter is plugged in, there may be a probleme with the adapter. [have it tested. the cords fray easily neer the ends... easy fix.] If the adapter tests good; there maybe a probleme with the DC input [being loose or having bad contacts... you'll need a good soldering gun and a steady hand to fix this] or it could also be a bad or dirty contact between the baterry and dvd [ gently clean with extra fine sand paper ]

hope some of this helps anyone having this probleme.

there is a charging lite [red]in the back of the unit it is blinking when charging