I've just added a turntable to the system. Through one zone, no problem. Through two, three, or four zones; dropouts to point that it's unlistenable. I tried the "fix" of changing the compression to compressed. That didn't help. The Sonos stream is compressed enough when playing services like Spotify. Part of the reason I got a turntable was to bring back the deep, full sound of vinyl. I will tried switching the input to the AirPlay device instead, because I read that it buffers more. That helped some, but did not solve the drop out issue. Set it to uncompressed and AirPlay. Actually, when it does cut out, it cuts out on every device except the Connect that the turntable is directly plugged into. My setup at the the turntable is; Turntable Preamp Line out, Connect line in, Connect Line out to Amp for that zone. Wireless to the Connect Amp in the closet. I can hardwire a CAT5 to the Sonos network instead of wirelessly connecting if that will help. I need to call and submit a diagnostic report, but looking for an advanced using that has solved this problem that may know something that works.
FYI; my Sonos systems consists of (1) Connect, (2) Connect Amps, (1) Playbar + Sub, and (1) Play5.