Cannot hear master when syncing

Hi all.

I’m trying to sync a 128 and 133 together, though whenever I follow the instructions to do so I cannot hear the master PO, any idea what I could be doing wrong? Just using a normal patch cable between the two. Have tried turning the volume up on the master and switching which one was the master/slave.

also just noticed that the volume on the megaman is kind of a bit lower than the street fighter which is pretty loud. I was pretty excited to use both of these together but trying to hear them both has been a bit of a mystery at this point lol. any help is appreciated.