Thank you all so much.

I am using USB cables on Nokia, HP, HTC, Samsung devices. I am thinking the cheapo usb-us plug adapter has a Amp limit, which seems the most obvious reason? It does not carry any spec, but assuming it is limited to 1A, for example, than Voltage difference would explain it all. Also, that adapter is the only different variable.

What do u guys think? Does this make sense?



Edit:
To be more clear, I am not using the original devices AC Adapters. They all came with EU plugs.