Just set up new TBT3-UDZ. Monitor attached to Display 2 intermittently and randomly flashes or loses connection. Have tried in both HDMI or DP with two different monitors (not identical monitors). Have seen similar posts and attempted basic troubleshooting from those posts.
By random, can occur in 30 seconds, 2 min, 2.5 min. But is is recurring and not in a discernable pattern.
Additionally, it would appear that one of my external drives occasionally disconnects and is rediscovered, opening up a new File Explorer each time.
Dock is connected to a new LG Gram 15 (i5, iRISxe), a new Samsung 34" (Display 1 DP) and an AOC 27" (Display 2 HDMI).
Thank you for contacting Plugable support! Sorry to hear about this issue. I’d be more than happy to assist you.
Unfortunately, we’ve had reports from other users with LG Gram systems that are having similar problems with displays through the dock. We may be unable to resolve the issue with your setup as we’ve been unsuccessful in resolving these issues with the other LG Gram systems so far. If we’re unable to help with this system we’ll need to likely issue a return for a full refund. However, your LG Gram model is a slightly different variant that we’ve not encountered yet. So I’d like to try to get some additional information to see if there’s anything we can do here.
We have a troubleshooting tool that helps us find out what is going on in situations like this. Please plug the dock with your devices attached to it into your computer, then go to this page and follow the instructions there:
I don’t think this is specific to LG displays. It is exactly the same issue with my NEC PA241W with DP connection. I looked up and found that PA241W is DP 1.1a compliant. However, the TBT3-UDZ is DP 1.4. It seems that TBT3-UDZ is having difficulties negotiating a stable connection with the older monitor on DP 1.1a specification. However, the same monitor worked perfectly fine on Lenovo Thunderbolt 3 Gen 2 dock without any issue (in USB mode).
Additionally, this problem only exists if you are connecting the TBT3-UDZ to a USB-C host. In my case, it is a Thinkpad T14s Gen1 AMD. If I connect the dock to an Intel based system with Thunderbolt 3, the exact same monitor works perfectly.
TBT3-UDZ+DP1.1a monitor+USB-C connection together seems to cause the issue. I have no solution other than staying with Lenovo TB3 Gen2 dock for AMD based laptop.
@etha2 It’s not an LG display problem in this case, rather, we believe the original poster @trlane is encountering issues with the Iris Xe graphics in his LG Gram laptop or some other compatibility problem.
I would recommend for you to email us at firstname.lastname@example.org so we can address your issue separately. We have a troubleshooting tool that helps us find out what is going on in situations like this. Please plug the dock with your devices attached to it into your computer, then go to this page and follow the instructions there:
I don’t think this is a USB-C only issue as I’m having the issue with my 2018 MBP, which is connected to the dock via thunderbolt. I’m using two NEC PA271Us connected to the dock over DP. The connections are all firm, however, the monitors will not infrequently flash off and then usually come back on in ten second or so.
My MBP is running MacOS Big Sur. This issue happened under the 11.2 point release and has continued under the 11.3 point release.
I’d be happy to submit diagnostics if you give me a ticket no.
Sorry to hear you are seeing issues with your Mac system and our dock with your displays blacking out.
We know some Macs have been having troubles with multi-display since about macOS 11.1 with various USB-C or Thunderbolt 3 devices. We’ve seen issues ranging from incorrect resolutions and/or refresh rates, flickering/black screens, or an inability to recognize more than one display after waking from sleep. We’re currently testing with 11.3 to see if there’s been any improvements and can confirm that some display issues are still present.
For Mac, there is not much that we can do at this time until underlying OS issues have been resolved, but I can recommend the following:
Plug the dock back in to the Mac and see if the behavior has improved
If that doesn’t help, feel free to email us at email@example.com and that will create a new ticket. Please include a brief description of the problem and in addition, we have a troubleshooting tool that helps us find out what is going on in situations like this. Please plug the dock with your devices attached to it into your computer, then go to this page and follow the instructions there:
@etha2 We had replied to you via the ticket you have open with us on 4/13 but have not heard back. We will be happy to assist you further, simply reply to our most recent email and it will automatically reopen the ticket.