Hi Jim,
Any resolution/updates about this problem?
I am also facing similar issue with linux usb audio gadget driver. It works fine (gets enumerated & USB audio can work) with Linux PC host.
However, with WinXP host (usbaudio.sys), enumeration fails with same status as what you have mentioned i.e. usb composite driver installation is fine but USBAudio installation fails with error code 10. The usb anlyzer log shows no error in device reponses/descriptors, enumeration goes past get_config, set_config, set_interface(iface=1, alt=0) & then followed by repeated get_string requests many times before it stops. set_inteface(iface=1, alt=1) which is my ISO out interface never gets requested by host.
Shall appreciate if we can sync up updates about this issue.
Thanks,
Rahul