You might have to build to the device, then unplug the lightning connector. It’ll disconnect the output to Xcode, but when you re-run the app it will have sound. Nothing to do with the kit, just a common issue.
I dunno, I just tested in both the Simulator and my device (Grassy Hills demo). Sound playing normal. Same build specs. I bumped it up to 11 just to be sure, but as the kit really doesn’t require anything iOS11-specific, I’d recommend you Target iOS10.2 . Still only about half of users have upgraded to 11, so there’s no need to exclude them as potential players.
This is the awkward part where I have to ask if your volume is turned down or in silent mode =)