As Jesse says these Dingoos are not built to the same standards that PSPs and DS's are. And so some consoles have some isues that others dont, and its all to do with build quality.
And so i guess the same hit/miss can occur with the chargers.
I only used mine 2 times and noticed it get a bit warm but not hot and my Dingoo a bit warm too.
I used my PC and PS3 to charge the Dingoo but they do take longer.
But as i said before a Motorolla Mobile/Cell Phone Charger worked fine for me, so Phones that have the same USB (B) Connection as Dingoo, you should be able to use their chargers.
Or even PS3 Pad Docking Stations.
The best way may be to get a decent quality USB charger, i got one from a popular electrical retailer and use that to charge my Dingoo and other USB devices from now on.