I’m looking at cost-effective ways to adding my already-installed wired outdoor speakers to my new Sonos system with Playbar, three Ones, and Sub. The Amp is not in my budget right now (not after just buying all the other equipment) so I’m on eBay looking at other items. I’ve found a used Connect (ZP90) that looks like it will do the job as far as plugging in RCA cables and connecting, but I’m concerned with it being an older legacy product that it will not work. I don’t care about using the S1 app versus S2 app, I just want to be able to use my living room (Playbar, Sub, two Ones), my kitchen (One SL), and my outdoor speakers to work on one network instead of switching to a separate bluetooth setup. Thanks in advance.