U2720Q, MacBook Pro, USB-A ports not working

I have just experienced the exact same issue this morning. Haven't changed a thing since it was working yesterday, Have you had any luck solving the issue?

MacBook Pro 16" and U2720Q

- Erik

Hi Erik,

Sorry for the late reply. It’s working now. I just took out the USB Type-C cable and plugged it back in and everything seems to be working now. Not sure what the issue was but it hasn’t occurred again.

Shiv

Hi

Thank you for taking time to reply! (and apologies for me not noticing

My monitor was working on and off, but now one of the usb-ports on the back has stopped working completely both with my Mac and my other Dell-laptop

I think I will have to return it

/Erik

I've also problems with the build in USB-hub. The USB-hub stops working after a while. it happens multiple times a day. Most of the time i can solve the problem by turning the monitor off and on again. But in some cases all the usb-devices stops working on my macbook and i have to shutdown my macbook. This issue doesn't effect the screen quality at all.

To poweroff the build-in hub, i made a change in the OSD-menu, under 'Personalize' and set 'Other USB-charging' to 'On during standby' and 'USB C- charging to 'Off during Power-off'

My setup: 

• Dell 2720Q, firmware: M2T101
• MacBook Pro 13" 2020 model, macOs Catalina
• Devices are connected with USB-C PD cable.
• USB-devices; Mouse and networkcard attached to the monitor. (USB-A). Problem exists also with an USB-c hub connected to the port on the left of the monitor.

If i connect my peripherals to an dedicated USB-C port on my MacBook instead of the USB-hub in the screen, i have no issues at all. So my conclusion is that the problems are not caused by my peripherals.

I try to reset the NVRAM and PRAM on my MacBook, i red in another topic that could maybe help.
See here how you can reset it.

@jam93 The issue has occurred a few more times since my post however each time I simply disconnect the cable from my MacBook and re-connect it and it resolves the issue. I’m still not sure why this happens though.

Shiv

Unfortunately, resetting the NVRAM or PRAM doesn't effect. After 2 good days, the problem returns!

Update:

There is a (not confirmed) macOS bug 10.15 or hardware problem in the MacBooks Pro/Air 2020. It can't properly handle USB2 devices connected to an (internal) hub. Devices can stop functioning out of the blue.