This usually indicates a catastrophic failure of the modem. The quickest way to diagnose this problem is to unplug the Ethernet and ADSL connections and cycle the power. When the modem comes back on if, after a short diagnostic period (2 - 3 seconds), the lights continue to behave in this manner, you most likely have an unusable modem.
The only known solution is to replace it. Apparently an incompatibility between the Enternet 300 software (at least version 1.5b) and the SpeedStream 5360 causes it to enter this catatonic state.
Enternet functions known to trigger this problem include:
