multicast objects socket error "can't assign requested address"

Hi there forums,

I need to receive UDP Multicast data into max but am having trouble doing so. Using mxj net.multi.recv every time I go to join a group or port I get "net.multi.recv: socket error. java.net.SocketException: Can't assign requested address
Have you already joined that group?"
When I try to leave a group or port I get "Are you sure you were a member of that group?"
The problem is the same with all of the multicast objects including multi.send and maxhole.

I'm running a mac on OSX High Sierra and think that might be part of the problem? I replicated the problem on a machine with the same operating system but didn't have any trouble with a machine with an older OS.
Is there something wrong with the way I have Java installed? I'm running Java 8 Update 171 and haven't messed with it at all. Is there something I need to do on that end?

Any help would be greatly appreciated.