iPad stuck on 'enabling...' for audio output in Roon (ref#BODWK9)

I suspect that your iPad is running Roon Production version 2.60, while your Roon Server is running an earlier version (or possibly Early Access version 2.59).

See:

Unable to find Roon Bridge v2.6 from EA Roon Server v2.59 b1625 post-update (ref#1G6HUW) - Early Access - Roon Labs Community