Did you disabled driver verification prior to installation of the driver?     See following LINK --> How to Disable Driver Signature Verification (64bit windows 8.1 or windows 10)  ...

The "FiiO X3 & X5 USB Drivers" can also be used with the Fiio X3 2nd generation.   You only need to replace a few line in the "TUSBAudio.inf" and "TUSBAudioks.inf" files which are in the setup folder.   Under the [Models] section in both ".inf" files replace:   [_Models] "FiiO...