No Sub Woof Sound  

All of my speakers check out except my sub-woofer. No sound from it and the test tones do not sound. I took the speaker to a Circuit City and they tested it for me and it was good. Bought a new cable but still no sound. That leaves just the amp, right? Any suggestions or repair ideas?? Love this new forum.

I don't have the same settings but I did check and my settings are as follows:

LFE -10 (range 0 to -20)
SW - Yes/No (yes is on)
SW +6 (range 0 to +6)
Effect +10

The amp is a Sony with optical & coax sound inputs for Dolby , 5.1 & DTS.

Everything seems to check out.

UPDATE: It was the amplifier. The SW circuit is out. It was preceded by a loud hum which I thought was a grounding problem at first but when I would move it....the hum would go away. A technician says it will cost $179 to fix but Circuit City had a sale on a better model of Sony for $189......so a no-brainer. Set it up and everything works fine.