Malfunctioning Behringer x1222usb mixer

[Saud Salaam]

My behringer x1222usb has stopped working. Once plugged in the main mix led lights begin to oscillates/pulsate and every other led light blinks. In addition, once I hook the speakers up it makes this beat sound that sort of sounds like a kick thats in sync with the blinking led lights. I already replaced the power supply board. What else could be my issue? What would be the best guess according to all the symptoms I've given?