Surroundbar SDA subwoofer signal

murray21

I have used the SDA surround at and subwoofer for years...It has been a fantastic set. Recently, the subwoofer no longer receives signal from the bar (it appears solid green on the sub and bar as though it’s connected but no lows are broadcast through the sub). I have switched between the 4 channels and none seem to work. So the sub has power and appears to be connected but no sound through the sub at all. Contacted Polk CS who told me to reset the bar using a 16 second hold of the “source” and vol down button followed by a 16 sec hold of the vol up and vol down button followed by unplugging both. Problem is there is no source button on my bar..just power, mute, vol up, down, and remote. Any suggestions? TIA