I bought a used Tablet MID 7 without charger. So i tired to charge with some nokia charger 5.7V 0.8A and when i plug in tablet charger speakers on tablet was buzzing and displey light is losing energy for some % and in the same time on displey it says charging charged...every 3 seconds charghing then charged and all over again its charging with pauses. He charge it for 10 minutes full 100% but then battery hold on only 5-10 minutes. When i turn off tablet and try to charge it, then i dont hear speakers buzzing anymore. only i can see that red led is lighting. I read somewhere that when that led became green that means that battery is full charged but after 1 hour of charging he just stop charging and i dont see no more red led lighting and not green led lighting... I google it and found that tablet mid 7 is using 9V 1.5A charger so i will try to find it in shop. I guess that should fix my charging problem??? But the main problem i have is with speakers on tablet. When battery is "full charged" (on this not orginal charger) speakers is working but only about 2 minutes on the begining and after that they start to losing like some connection and they just stop working. I plug in headphones into the jack and i can hear sound but only on headphones, when i plug in off i still dont have sound on speakers. Then i put tablet again on charging and when it got about "full charged" then again i have sound on speakers but only about 2 minutes on the begining until they stop working. That is pretty weird because on headphones is working every time! What that could be? Is there only problem charger or something more?