I have a similar issue. I already reported here
Link
Also, I had to install somethings on the Nano, so I used VNC for remote desktop from my laptop. The moment I connected via VNC, it became super slow and when I tried to reboot, I could see only the NVIDIA logo and then just a black screen. I was still able to ssh via the Ethernet but it was really annoying. So, I re-flashed the card hoping that it might solve the HDMI and USB issue. I used this image to flash it on the sd card Link
But then HDMI is solved but now I can no longer do ssh since first I have to do some settings (‘share network’)
I have limited time that’s why I thought to create RMA. Would you suggest to create a RMA for quick workaround?