I have charged my X3 with a USB 5V 1A charger but I thought it isn't fast enough, so I bought a 5V 2.1A charger.
The problem is the 2.1A charger doesn't charge any faster than the 1A charger.
It took over 6 hours to fully charge from an (almost) flat battery but according to the manual with a 1.5A (or above) rated charger it should took 4 hours (forced shutdown charging).
How does the X3 detect how much current it can draw?
Is it using the USB "data" pins 2 - 3 for detection?
Did I buy the wrong charger?
What could be the problem problem?
The 1A charger has the USB pins 2-3 shorted.
The 2.1A charger has 54 kOhm resistance between the pins 2-3.