Disk Utility: Invalid Disk Label @ cksum mismatch

I have a WD external hard drive. I've been running the routine tests to make sure all my stuff is safe lately. In Disk Utility, I did Verify Disk on both the disk itself as well as the main partition, which is in the encrypted HD format.

I ran across this error on the partition:

Invalid Disk Label @[number] cksum mismatch

Which didn't seem very good. Resources online have close to no information, and I don't know what this is. It went away after I scanned again, but that is a common occurrence and other posters said that I should keep an eye on it.

I ran Repair Disk and it went without a hitch, but Verify Disk after that still showed the error.

I ran SMART Utility with the SAT-SMART Driver to enable SMART on external USB drives, it passed with 0 bad sectors and stuff.

Any ideas?

MacBook Air - Mavericks 10.9.5