USB-C Dock keeps connecting and disconnecting every 30 seconds (MBP 2016)

Every 30 seconds or so the dock will disconnect and reconnect to my MBP 2016 without touchbar. Originally I had plugged up my dual monitor setup which would flash every 30 seconds. I scaled from 2 monitors with a usb flash drive to one minor with a usb flash drive, to 1 monitor with no flash drive, to JUST the MBP connected to the dock with USB-C connector which should’ve charged my MBP. I still ran into the issue of connecting/reconnecting like clockwork - every 30 seconds.

Hi Brandon, thanks for posting! I am sorry to hear of this issue when using our dock with your MacBook Pro and I will be happy to help!

Thank you for the description of the behavior you are seeing. Just to clarify, are you using the USB-C cable that came with the docking station?

Also, would you be able to let us know the version of macOS that you are currently running?

Please let us know this additional information whenever you have a moment and we’ll go from there.

Thank you,

David W.
Plugable Technologies

David, I am currently running Sierra 10.12.3. And yes, I am using the USB-C cable that shipped with my dock.

Hi Brandon, thanks for the reply. We have witnessed similar issues on the MacBook Pro systems when using our dock where the connection is not stable, both on in-house test systems and from customer feedback. We’ve been investigating these issues with our Engineers and are searching for an absolute solution. Our belief is that the issue is related to signal integrity on the MacBook Pros. Some customers have been able to mitigate the disconnection/reconnecting behavior by connecting the MacBook Pro’s power supply as well as connecting our dock, but we certainly understand that is is not an ideal workaround.

One thing we have done is send pre-tested Thunderbolt 3 cables that have worked better to shield the connection from the potential interference and we have had positive reports from customers. I’d be happy to arrange for a pre-tested cable to be sent to you to see if the connection can be stabilized, if you’d like. Just reach out to our direct support email address at with ‘Ticket Number 171821’ in the subject line and with your Amazon Order ID number, the serial number from the bottom of the dock and your preferred shipping address in the body of the email to send the replacement cable. We will then be able to get the process underway.

Please be aware that the Thunderbolt 3 cable will likely be shorter in length (half a meter in length) than the current USB-C cable that you are using.

Thank you,

David W.
Plugable Technologies

To add to this… I am also using the same cable with the work around you guys provided. I am using 3x displays and now all it does is disconnect every 3-45 seconds… to the point that I had to disconnect.

Erick, please note that I am the original poster- not a Plugable representative.

I found that my issue was a UPS power supply that has a built-in battery backup and surge protector. Once I bypassed the UPS I had full connectivity to my monitors. Don’t get me wrong, I don’t enjoy not being protected but if it’s necessary that you need to have everything up in a timely manner, bypass any electrical boxes you may be going into.

Because of the issues that keep piling up with Sierra and my dock (not exactly Plugable’s fault) I think I am going to go the dongle route.

I’d like to again say that throughout the process, I have posted on here and sent in an email to the support site and both reps I have worked with have been EXTREMELY pleasant. I even have a second dock being shipped to me currently to test.

thanks for the info.