when i try to test the network it says no test servers currently available running a mac desktop on virgin media hub hard wired with an ethernet cable 

On the main sessions page, click the VIEW THE FEED button to see past and current sessions and public recordings.  

Recordings can be listened to from this page.    

There is a feature to listen in to public sessions, but this feature is currently disabled due to high demand.

You can create a private session using the QUICK START SOLO button.  Even during this session, you can invite others if you so choose.

You can create a simple public session using the QUICK START OPEN button.  Anyone can join--jam time!

Finally, with the START OR SCHEDULE button, you can see every setting available when starting a session, or even schedule a single or recurring session for the future.

You can find other sessions by clicking the FIND SESSIONS button on the session page.    Public sessions are listed here, as well as any private sessions created by your friends or that you have been invited to.