USB-UIRT zones not working

I bought two Smarthome 8170s emitters. I can not get the zones to work. I plugin headphones into the splitter I bought and I hear no sounds. I tried different splitter and that did not help. The serial number ends with a Z so I know that it supports zones. Is there a log somewhere I can check for errors? I am using Eventghost, the internal emitter works fine. I have selected the different zones in Eventghost but no go. I have checked the forums but have not found a resolution. Is there something else I can check?
Thanks in advance.
Thanks in advance.