denon 3300 subwoofer problem

I purchased a used denon avr 3300 and I can't seem to get the subwoofer working with it. No sound is comming from it when using the denon test tones. Unfortunately, at this point, I'm almost certain that the receiver is a dud however there may be something I missed along the way.

The subwoofer is connected to the subwoofer preout. I selected subwoofer "yes" durring setup and LFEs are sent to subwoofer only. L & R speakers are set to small.

The sub works perfectly with another denon receiver I am using. I've also tried a manual reset on the 3300 but to no avail.

Should I throw the towel in and conceed? Is there anything else I can try? Thanks.

Denon 3300
Denon 1602
B&W dm220
B&W dm303
B&W LCR 6 S2
Energy S10.2

Nope. It sounds correct to me (i had a similar Denon set up).