PS4 Pro 7000 Beeps when power cord is connected

I have an interesting situation. I have a PS4 Pro 7000 that beeps 3 times as soon as I plug the power cord into the unit. The unit is then completely unresponsive. I figure it’s a power supply issue, but since I don’t have a working power supply I was hoping someone who has experienced this can confirm. The power supply is the ADP-300CR. any help is greatly appreciated!