The USB ports on our Flash Pro and Flash Pro Plus powerbanks feature an automatic identification function. This means that when a device is connected, it will automatically start charging without the need to press the power switch. This is an upgraded feature compared to our previous model, the Flash 2.0, which required users to manually activate the charging mode by pressing the power button before each use. This may explain why you haven't encountered this feature before.
It's important to note that the original iPhone USB cable contains an internal circuit. Even when it's connected to the Flash Pro Plus and not charging any device, the iPhone USB cable acts as a charging device itself. This activates the DC circuit of the Flash Pro Plus, resulting in a slight power loss and a displayed output of 5V, as you have observed. Our testing has revealed that the iPhone cable is the only cable on the market with this particular characteristic.
To address this situation, we recommend unplugging your iPhone cable from the powerbank once you have finished charging your device. This will prevent any unnecessary power loss and ensure optimal performance.
If this article does not resolve your issue, please submit a request and a member of our Customer Happiness Team will respond within 24 business hours.