D5-300 is glacially slow

[ezplanet]

If you are sure you got a wrong delivery, please contact the service team for after sales service. Just find the email address from my signature.

To clarify, it was not a wrong delivery, but a wrong purchase, when purchased the two models are indistinguishable if not for the "C", that at the time did not seem to have any importance.

As I know now, the difference instead is significant.

[ezplanet]

I wish TerraMaster were more helpful.
Despite the name, it is a Chinese company, isn't it?

[TMroy]

If you are sure you followed all steps in the troubleshooting guide and the issue still persist, then you can contact the service team for warranty service.
12MB/s is far away from the normal speed value.