Are you able to post a screen shot of what you are seeing....or not as it is?

Can you play VST instruments , drum loops etc within S1 ?

I am not currently in the studio but I will get a few screenshots and post them tomorrow. I will try to describe it better anyways.
I have a mic feeding into input 3 on the Firestudio. The Firestudio is connected to the Mac via firewire. The first thing I do is check universal controller to make sure everything has been recognized. When the Firestudio is recognized I turn on the mic and talk into it. I can see the sound level increase in universal controller. I then switch over to Studio One 4. Within Studio One 4 I set the audio device to the Firestudio. I then add a track to Studio One. Before I do anything I set the proper inputs and outputs (such as creating a mono input and assigning input 3 to it). At this point once the inputs are set properly I should be able to see a sound level increase within the Audio I/O screen but it shows no sound level changes. Now with the inputs set properly I go to the track and set the 'In' to the new input. I select the record button on the track as well as the monitor button on the track. I should be able to hear (monitor) the output at this point as well as see the audio level change for the track. There is no output at all as well as there is no visible sound level changes. With this exact setup done of a separate computer (my Laptop) it works fine but not on the studio computer.

Try to open a new song, and use the existing template for your device. This would rule out any mistakes in I/O setup. If you still aren't getting anything, we may need to look at the firewire connection on the PC. You will want to locate the make and model of the firewire card/chip to go down that path. If the device works on another computer, the firewire connection on the second computer may be at fault

I used a template that is know to work and it works on the one Mac but not the other. I highly doubt it's a problem with the firewire card/chip. Universal controller does recognize both the interface and that there is audio. Just using universal controller I can output directly to a hardware output to hear sound but I need universal controller set to allow the daw to do the work for what I need.

TLDR
Not an I/O setup error.
The audio interface is detected by the computer.
Sound is noticed in universal controller.
Still can't get Studio One to register there is any audio.

The fact that you see audio activity in UC would not rule out a firewire issue. That is just showing the hardware direct monitoring. The driver, contained in UC, adds the PC/Mac component to the mix. What you want to make sure of, is that the PC/Mac properly recognizes the FSP. Verify through device manager on the system.

What version of UC is installed on the Mac? High Sierra introduced some install challenges. The link below shows how to navigate through them.

Also, how exactly is the FSP connected to the Mac? Direct Firewire (is it 800 or 400), or are you using a TB to FW adapter?

Also, I would try and set up a new song, using a new template for the FSP. You want to rule out Items one at a time, and start with a clean slate. If you are using a firewire 800 connection, make sure that the cable is specifically rated for bilingual, and make sure that the cable is good.

https://support.presonus.com/hc/en-us/a ... -OSX-10-13