I have a new behringer (although I doubt its authenticity) UCA222 and using this one I cant replicate my problem, so it looks like my original is blown/worn out. It is strange that it works perfectly while using on my ipad mini on 9.3.5. Anyway, Ive closed my apple dev bug report (including the sysdiagnose logs for completeness).
Ill pop a label on my old uca222 saying ‘not ios 10 friendly’. Sorry if I hijaked this thread, my intentions were good!
rich