Logging on to an audio ad?

Not twenty minutes ago I returned home and logged into my PC to be "greeted" by an audio advertisement from Qwest through my (RoadRunner) cable connection.  Basically what it containd was some inaudible chatter at the beginning, like random hallway noise, and then "Did you know you share your cable internet connection with everyone around you?  Qwest High speed internet services are available in your area."
And now I cannot replicate it by logging back in after double checking my firewall and even disabling it.  Has anyone ever had something like this show up?