And you said you already tried a different USB cable, right?  And a different USB port?  If so, yeah, I'd be inclined to place the blame on the device itself.  However, it doesn't explain why manual Verifies worked, why Verifies only failed on backups, and why image backup Verifies didn't fail.  Still you can't argue with results.  If connecting a different device doesn't have issues, you can pretty much blame the other device.

The storage device was failing.  Several disk utilities started to indicate that.  Replacing the storage device has returned backups and verification to normal.

Macrium was very responsive and passed along the following possible solution.  I had already replaced the storage device when I received their reply so was not able to give it a try.  I'm including it for those who may want to see what they said.

"After looking at the logs and the system you are running, we believe this could be an issue with multithreading.

With the new backup engine, we also introduced a new verification engine which also utilizes multithreading. When the verification process takes place we believe the CPU can not handle the load and is causing the verification process to fail.

Can you please enable the legacy version of the software by following the instructions below and see if this allows you to verify the file after the backup has been taken?

Open the registry editor and create a new folder called verification under HKEY_LOCAL_MACHINE\SOFTWARE\Macrium\reflect and add the registry key below.

Path: HKEY_LOCAL_MACHINE\SOFTWARE\Macrium\reflect\Verification
Key: Legacy
Type: DWORD
Value: 1

Once this has been done can you please perform another backup or wait for the next scheduled backup and report back to me? "