My Sonos has an audio delay setting that defaults pretty high. Have you looked at that setting?

Thanks, but are you talking about the app or the physical remote. My issue is 100% in the remote app on my iPhone. The remote works fine.

Okay, I’ll give that a shot, but I have no IR in my system…

My only issue is with the Apple Remote App on my iPhone. The Apple Remote itself sets the volume just fine.