Mine is unsually in slumber only until the lower frequencies are sent to the sub. When I listen to music in lower levels I do not even see the sub light go from amber to green. But the moment I crank up the volume the sub light changes from amber to green. I have my crossover frequency set low to like 60 or even sometimes at 40 for music listening. There are times when I shut off the sub crossover when stereo music listening and the light stays amber all the time. I know this might be a stupid question but is your receiver setting for your sub set to on? Even when amber if you reconnect you wire the sub would change from amber to green when you plug in your sub cable because a signal is detected by the subs amp. You can also bring up your crossover on your sub to like 80Hz or 100Hz. I am not sure the type of music to listen to but most should actuate the sub. Try some church pipe organ music. That definitely goes down to the reaches of 20 something hz. at times.

Saturn

http://www.quadloft.com/hometheater- new HT