UD-CAM+MacBook Pro+Acer B276HUL: screen going black randomly

Hi,
I am using a MBP 15,1 with UD-CAM and an external acer monitor (B276HUL).
The monitor is seen by my Mac but occasionally goes black while using my computer, and it comes back only power cycling the monitor or disconnecting and reconnecting the USB-C cable that goes to my Mac.
This is quite disruptive when working, and I have observed the same behaviour when connecting a DELL screen rather than the ACER, which presumably rules out a firmware update on the monitor side.

Please help?

Hi There,

Thank you so much for reaching out to us, I am sorry to hear that you are running into this issue, but I would be more than happy to assist!

Just to make sure I have all of the right information, are you utilizing the original USB-C to USB-C cable that came with the dock, or an alternate cable?

Does the same issue occur no matter which port you utilize on the system?

Thank you for your patience,

Marc

Product Owner & Technical Support

www.plugable.com/support

Hi,
this is indeed with the original cable and independent on the port I’m using on the laptop.
I own two UD-CAM, and both units show the same behaviour, which most likely excludes also a faulty unit.

Hi Alex,

Thank you so much for letting me know! This particular behavior normally is associated with either the cable, the dock, the displays, or the system itself. If the issue occurs on multiple displays and HDMI cables, then we can rule out the problem being associated with the displays. We have never seen this behavior before on this particular system, and the UD-CAM has been extensively tested in-house with your particular system, and we have not run into any of the same issue.

Since you have two UD-CAM docks, and the same issue occurs on both, are you utilizing the same AC Adapter and USB-C cable when connecting the docks, or is the problem occurring on both docks with the same cables?

Thank you for your time,
Marc
Product Owner & Technical Support
www.plugable.com/support

Hi Marc,
thank you very much for following up on this. The two docks are completely independent: I have one at home and one in the office and they have their own set of cables and power supplies.
I also verified using different USB-c ports from my laptop and the behaviour remains.

cheers,
Alex

Hi Alex,

Thank you so much for letting me know! This throws a particular wrench into the equation, as the only common denominator between the two docks seems to be your system, and not the displays or the docks.

Just to make sure I have all of the most up to date information, when you have a moment, could you please visit www.plugable.com/support/plugdebug and download and run our diagnostic application, and then email the .zip file that is created to support@plugable.com? Please include “Ticket no. 267328” inside of the subject line so that we can keep all of your information in the same place.

Also, what other devices do you have connected to the dock when this issue occurs?

Thank you for your patience,
Marc
Product Owner & Technical Support
www.plugable.com/support

Hi Everyone,

We attempted to have Alex submit additional information associated with his issue, so that we could work on the next steps, but we have not received a response back. If Alex would like to continue to troubleshoot the issue he is experiencing, or anyone else is running into the same issue, please do not hesitate to reach out to us directly at support@plugable.com.

Thank you for your time,
Marc
Product Owner & Technical Support
www.plugable.com/support

Dear Marc,
I’m reporting your reply here for reference to other users:

Thank you so much for reaching back out to us, and running our PlugDebug application and sending over the output. Based on the log files, the problem may be related to the individual graphics card version your system has, and the GPUSwitch that occurs when the system is asleep. Based on the information you supplied, the problem only occurs when the system is slept or locked, and then is waken. What could be occurring is the system is attempting to “switch” the GPU once it is asleep, which is causing the display to disconnect, and then not properly send the EDID information associated with the resolution you have the external display set to. If you set the resolution on the display to 1920 x 1080, and then utilize the dock normally, does the same issue occur?

What types of applications were you utilizing before each of these issues started to occur?

My reply:
I tested setting the display resolution, and the problem remains. The example I provided you follows a fresh plug-in of the dock with basically no applications running other than a browser (you can check that on the logs provided).

Hi Alex,

Thank you so much for posting our response, and yours on the thread! At this point, we are concerned that the issue is directly associated with your system, as the problem you are running into is not one that we have been able to replicate with multiple docks on a similar system inside of our testing labs. The problem may be directly related to how the internal PD/Alt-Mode chip communicates with your system. This may not be something that we can fix, and since the problem is occurring on two different UD-CAMs (and is not prevalent in our internal testing system) we have two options:

  1. Offer a complete refund for both docks, as we do not have any additional fixes, firmware or solutions that may resolve your problem

  2. Send out a replacement unit of another dock with a lower Power Delivery rate (60W instead of 85W) and see if the same issue occurs.

Please let me know how you would like to move forward, and I would be more than happy to assist!

Thank you for your patience,
Marc
Product Owner & Technical Support
www.plugable.com/support

Hi Marc,
let’s try with the replacement unit and see if that works. Could you contact me via email to define shipment details etc?
cheers,
Alex

Hi Alex,

Thank you so much for reaching back out! If you could, please email us directly at support@plugable.com, with “Ticket no. 267328” in the subject line, and please provide the Amazon Order ID Number associated with your purchase, and a confirmed shipping address, and we can work on the next steps.

Thank you for your time,
Marc
Product Owner & Technical Support
www.plugable.com/support