Device doesn't enumerate with STM32H7xx

[wolfmanjm]

Has anyone made this work on an STM32H743? (Devebox) I have ported it as required using this very simple CDC example. My linux PC sees a new device but is unable to enumerate it.

[346066.977184] usb 1-9.1: new full-speed USB device number 76 using xhci_hcd
[346077.503187] usb 1-9.1: device descriptor read/all, error -110
[346077.701240] usb 1-9.1: new full-speed USB device number 77 using xhci_hcd
[346088.213259] usb 1-9.1: Device not responding to setup address.
[346088.421332] usb 1-9.1: Device not responding to setup address.
[346088.629204] usb 1-9.1: device not accepting address 77, error -71

Stepping through the code I am getting the request and appear to be sending the reply but the send is either incorrect or not happening at all. I have checked the clocks, I am using the USB_OTG_FS device. I do have the HAL version working ok for the CDC, but I'd like to have a composite device so that is why I am trying to get this to work. Thanks for any help or pointers.