DDJ-1000 Firmware 1.12 Update Problem: Echo

Update of DDJ-1000 firmware to 1.12 has resulted in all audio input (digital or analog) being output TWICE within a split second, effectively an echo.  Doesn't matter whether I'm playing a record or a digital track.

The update is shown in Rekordbox as having been successful.  I've tried every remediation I've been able to find, including all the steps in the Firmware Update Guide.  I've re-installed the driver, and the firmware, in different sequences multiple times, all with the same result.

I've reached out to Pioneer support directly and they're looking into it but I'm pretty desperate here.  Sharing in case anyone has had a similar experience, and/or there are any ideas for remedies out there in the community.  Thank you!