Oppo Sonica Damaged Firmware? - USB ports Dead - HELP!

Both USB ports have died on a modified Oppo Sonica DAC I bought about 6 weeks ago.  I am pretty sure it's a software and not a hardware issue (I'm guessing corrupt driver).  When this happens on any of my Windows PCs it's a relatively straightforward fix, re-install any damaged drivers.  Problem is I have no idea how to do that on the Oppo and I can't find anything on the internet about it.
I can download the latest firmware version but can't even attempt to install it because it won't read a flash drive from either USB port.  I figured this was a long shot, but the A'gon community has been so helpful in the past I figured I would at least ask.
any help GREATLY appreciated.
Thanks.
Ian