Help! Adobe Media Server receiving data but not sending it out. Worked perfectly just days ago.

We're using Adobe Media Server (v 5) to stream video on an Amazon S2 (CentOS 6.3) server. It has worked perfectly for months (utilized several times a week) but suddenly, today, has stopped working.

As you can see below, the Media Server is receiving information but not sending it out. No changes have been made to our setup whatsoever.

Any idea what might be happening? Thanks in advance for any help you might provide!