Hard Drive will only mount when connected through keyboard USB hub

I have a powered USB External Hard Drive that won't mount when plugged into the ports on back of my iMac 27" (Late 2014) running Big Sur 11.7.1. It is not detected in Disk Utility at all when plugged into one of hte ports on the iMac. The strange thing, however, is the drive mounts fine if I plug it into one of the USB ports on the keyboard which is then plugged into the iMac. I have tried all of the USB ports on the iMac and the computer won't detect the drive on any of them, only when plugged into the USB hub on the keyboard. The drive works fine on other computers. Anyone have any ideas?