I have a problem with only one bus working at a time for recording and I am not sure why it started doing this. I recorded with it just fine a month ago and when I went to record last week only one bus would activate. I can assign all the different inputs to the correct channel but the main channel with the little orange speaker is the only one that will work. I noticed that the perforated lines that usually connect the buses are gone? Is that why the other channel will not give any input level? If so how do I reconnect the different bus channels?
Can you please expand the Device Port column so we can see the full name for the port? What version and build of Studio 5 are you using (Cubase menu, about)? What Mac OS are you on?
The most likely issue would be that Studio 5 is not supported for 10.9. The last Mac OS it was supported for was 10.7 Cubase Studio 5 | Steinberg
My best suggestion would be to either revert the OS to 10.7 or purchase a new retail copy of Cubase Pro 8 for use on 10.9/10.10.