My bad , yes I took it off the box and straight into to the ender 3 pro, haven't done anything else.
Really silent, until I flashed the octoprint and connected it, got something to print and the bed was going crazy.
The printer has a power switch. Without a USB connection, this switch controls the power to the printers heaters, steppers, and electronics (control board).
When you connect a USB cable to the printer, the electronics are (unintentionally) powered from the USB cable. If this USB cable is plugged into a RPi, then the power supply for the RPi may not have enough extra (or reserve) power and the RPi may exhibit symptoms of undervoltage, etc. There is also no way the printer's steppers or heaters can work with the limited current supplied by the USB cable.
Because of the parasitic drain on the RPi power supply, it is common practice to prevent it by cutting the 5V line in the cable or taping over the 5V pin in the connector. Now the printer only works when the printer is powered on.
I'll let you search these forums for details. I believe there is a topic devoted to this process.