Within my last 2 sessions, my audio has turned off. The first time I restarted, and it began working again. Then the next time, it did the same thing. I did some diagnostics and the Status on my Audio Controller says it "Recieved Master Abort." (If that even means what I think it means..logic says my computer shut off my audio for whatever reason.)

What could be causing this, and what should I do?

Update: If I log off, my sound returns..I don't even have to restart.

This is usually a connection problem to your speakers
You should check all connections are secure

Edit:

Also your mobo description Dell A01
Can you please re-confirm the model, it should be written on the back, or in any Dell documentation you have.

Maybe a bit more detail could help us a bit, could be a driver issue or perhaps a faulty sound card, or even what kimsland suggested with a bad connection at your speakers .