TBT3-UDV connected to new MacBook Pro (latest 2108 15" with Mojave); Mojave gives warning notification


Notification says “Cannot use Thunderbolt accessory; Connect accessory to a Thunderbolt port on this Mac.”
I have audio connected, an iPhone 10x, a nd currently one 4k monitor via USB-C to HDMI. Everything seems to work so why the warning.



Thank you for contacting Plugable support! Sorry to hear about this issue. I’d be more than happy to assist you.

Are you connecting the dock to the computer using the half meter 40Gbps Thunderbolt 3 cable that the dock shipped with? If not, be sure to swap back to the stock cable as just any USB-C cable is not going to be compatible (example: the white USB-C cable that came with your Mac is not compatible).

Please don’t hesitate to let us know of other questions.

Thanks again for contacting Plugable support and best wishes!

Joshua Henry
Senior Engineer
Plugable Technologies

http://plugable.com | http://performance.plugable.com/


Thanks for the reply. I was using a longer cable from jsaux.com. Is there a longer cable I can use or am I limited to the half meter cable? Perhaps at least 1 meter? Or a little more?
Thanks for the response.
BTW, does Plugable have a powered USB-C Powered hub that can expand the capabilities of the TBT3-UDV. The 4 USB connectors on the back are not powered. I have a USB 3 WD My Passport Wireless Pro that I have always used with my 2012 MacBook Pro and I would like to connect that through the TBT3-UDV.
Thanks again for your assistance,


Sorry for my delayed reply over the weekend! Thanks for the info. I looked at the cables from jsaux.com and confirm they are only rated for USB-C.

Currently due to Thunderbolt 3 and its incredible bandwidth capabilities, the longest passive Thunderbolt 3 cable supported will be a half meter to about .8 meters. We’re currently investigating the release of longer cables, but we’re not ready yet. For the moment, the only option for a longer cable would be an “active” Thunderbolt 3 cable which should allow up to 1 meter at the full 40Gbps. Unfortunately at this time we’re not carrying active cables, but they are available on the market.

Regarding the USB ports on the dock - they are powered and provide up to 900mA which is the standard for USB 3.0. As such, they should be able to power your WD Passport drives via USB. Please note that if the dock is not connected using a Thunderbolt 3 cable that the USB ports on the dock will be inoperable.


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