I can't find a Yamaha NS-W210, but I can find an NS-SW210. It appears to have a single LFE input (as well as a gain knob and a power button). The Onkyo AVR has three different pre-outputs: L+R main-channel out; subwoofer out; and Zone 2 out.
OP, are you running a connection from the output circled in red (below) on your AVR, to the input on the sub?
- If 'no', try this connection.
- If 'yes', then perhaps you need to: try a different cable; raise the gain on the sub itself; check some settings in the receiver's speaker set-up menu.
Thanks guys, you are right, I had it plugged into standard left channel pre-out as eljaycanuck's diagram suggests. Plugging it into the sub pre-out fixed things, doh! Btw, I bought the receiver from Accessories4less. Have you guys ever bought from them before? And if so, turnouts were good? Thanks again for all your efforts in helping out.