Super slow transfer in/out of 5tb ultra to/from 4 tb my passport

I’m using a “MY Passport” 4 tb drive as a main storage drive, and I copy it to other WD external portable drives for backup. I also have a 5 TB Passport Ultra, and it refuses to download or upload at faster than 10 MB per second when working with the 4 TB drives. All four of my 4 TB drives run at 30+ when talking to each other. How do I fix this?

Hello,

Please refer to the following KBA article: Common Causes and Solutions for Slow Network Data Transfer Speeds