Slow USB Charging connected to Laptop/Desktop

[atherosxd]

who else are experiencing slow USB charging when charging using the laptop/desktop. Since I upgraded to wp8.1 I noticed that it is much slower than before and has a tendency to decrease the battery percentage when using it for a couple of minutes.
sorry for my bad english.

 

[Ashalinia]

This happened before 8.1 especially if you were doing intensive stuff on your phone while it was charging or have the brightness up high. At least it did to me.

 

[Danjp]

USB ports usually have low amperage (<.5) most smart phone chargers are 1 amp, I use the kindle fire 2 amp charger when I really need to charge fast.