Sonos port L/R unbalanced female RCA’s out to Behringer flow 8 -mixer/ XLR inputs male or female in optional. From mixer XLR out to QSC k12.2 PA speakers (a pair) pig tailed to Ks 118 subs (a pair). My Problem is converting the two unbalanced RCA ports to one XLR cable with the other end of cable connecting XLR connector plug. Is there a way to do this with good and correct results. The run is long and goes from inside my house 75ft to outside mixer then it runs another approx. 150ft to PA system. So I will be buying 14/4 premium direct burial cable for this and will have to add my own connectors to the cable. I spent hours online, trying to figure this out without any clear and cut results. They tell you how to do it. They have a conversion connectors for it, but no one will commit to saying that it works and is correct without losing anything. I just want a balanced good signal that connects when I’m done. If connectors are soldered and wired correctly is this possible? Is there a converter out there that (if needed) will work?