Currently, I have a Sony SA-WMT300 soundbar and subwoofer. It has an optical cable that runs from to the TV to the soundbar. The soundbar is wirelessly connected to the subwoofer and neither have RCA ports. I want to use both with the Sony STR-DE975 receiver I have. I found a converter for RCA to optical for the soundbar but I can't find a way to connect the wireless soundbar to the receiver. Then I got the thought that I could combine the channel for the soundbar (which I would use as the center speaker) and the subwoofer into one RCA which would convert to one optical cable and go into the soundbar. It would then get separated and sent to the subwoofer. Would this work or do I need to buy a different subwoofer?