WD (new) Blue 6TB recurring buzzing noise

I have a WD Blue 6TB drive (the new 5400RPM variety which has replaced the green drives) which I am running in a Synology NAS. Every 20 seconds, the drive makes a buzzing like noise, as if reading/writing a bit of data. This seems to occur with the drive in the NAS, but also in a PC, but only when idle state. When reading/writing data normally, the recurring noise disappears. I have tried to run WDIDLE3 to test and check whether it could be the idle timer, but the program does not seem to work with the new blue drives. Some searching seems to indicate that I am not the only one with these noises on the new blue drives, so perhaps this is normal. I have added a link to a video with the noise, which you can hear at 2s and 23s https://youtu.be/yE7j58mj19U Any insights would be much appreciated!

That sounds like head parking/unloading to me. Have you been able to run a hard drive health test using WD Data Lifeguard Diagnostics for Windows just in case?

Yes, the health test came back without any issues. It does sound like head parking/unloading, but surely this shouldn’t be happening every 20s and will damage the drive in the long run? Also it’s driving me insane as the drive is sitting on my desk!