There was some strangeness in beta 5 and external audio.
Am I correct in thinking that the Apogee Jam has a power input (e.g. over Lightning)? Try connecting it to your iPhone before connecting it to power. That's what made my (albeit different) legacy audio solution work.
All audio interfaces connected by Lightning directly doesn't work on iOS 11 even GM.
But if you use USB camera adapter then will work very well. I tried it.
Does anyone have a fix for this issue? I was in need of using my apogee jam tonight not realizing that the updated iOS 11 does not support the interface.