Has anyone else noticed this? I have mine set up without the LFE on an Onkyo 809 and even with the Receiver off? Per the owners manual this should go off once the speaker stops detecting a signal. It's no big deal just wanted to make sure no damage occurred to the speaker.

No worries - the green light can take up to an hour or longer after the system is shut off to go out.. The power draw during this time is very very small.