I don’t own this charger, but just reading through HKJ’s review of it, he mentions that this charger can ask for a lot of current from a USB wall adapter (up to 4A), which most wall power adapters can’t deliver, so I would make sure you have a robust USB wall power adapter that can maintain voltage at high current. He also states “The charger has some problems with a unstable power supply,” but I don’t know exactly what he means by it. Maybe ask him?
And yes, flydiver is correct that there are a lot of garbage USB cables out there with high internal resistance which will further reduce the amount of available current to your device.