Only get 4K 30Hz or no signal when using USB-C

Hi. I have a new work laptop a Surface Laptop 4 and use a Surface Dock 2 to connect two ES07D03 monitors. The issue I am getting is I only get 30Hz maximum in display settings on my Surface Laptop 4 and not the 60Hz I was expecting. The Surface Dock 2 supports 2x 4K60Hz monitors when using the surface connector

One of the selling points to me is that the monitor effectively acts as a KVM by the USB Hub switching upstream host when the source changes from displayport to USB-C. I have my Desktop PC plugged in using displayport and USB Type-B upstream port for the USB Hub. I then have my Surface Laptop 4 connected to a Surface Dock 2 and that in turn connected to my two ES07D03 monitors using the USB-C upstream ports. I get a 4K30hz video signal (this is the issue) when I change to the USB-C video source.

Some extra information on the setup. I have the USB Hub set to always on, the USB-C bandwidth priority as high USB data speed and the USB hub source set to select automatically as I do change between my work laptop and personal desktop when I finish work for the day. I have a Logitech Brio connected to the first monitor and a Corsair Virtuoso Dongle connected to the second monitor which has my Corsair Virtuoso headset, Corsair K100 Air keyboard and Corsair M65 wireless mouse all paired to it. I am using Intel Certified Maxonar Thunderbolt 4 cables which are backwards compatible with Thunderbolt 3 and USB-C 3.2. I am on the latest scalar firmware 107 and USB firmware 06A4 / 0A.89.19.02

Some testing I have done is setting the USB Hub bandwidth priority to high refresh rate, no difference. Using different cables. I have used Intel Certified CalDigit Thunderbolt 4 cables no difference. I have also connected my Surface Laptop 4 running Windows 11 and a Surface Pro 5 running Windows 10 directly to a third monitor without the dock using both the Maxonar and CalDigit cables. The monitor is detected in the display settings but windows won’t extend to the display and the monitor keeps stating no signal detected. The amount of testing I have done so far would suggest it’s the monitors not liking Surface devices.

I have raised a support ticket but I never get a response so posting this here if anyone else has any more ideas.

Some more information on this. I am using my Surface Laptop 4 with the Surface Dock 2

If I set my display settings to 2560 x 1440 at 60Hz this happens on the monitor.


I have now tested a two difference Surface Laptop 4s with the Surface Dock 2 and can’t get 4K60hz to either monitor connected from either laptop.

I’ve also tested both Surface Laptop 4s and a Surface Pro 5 directly to the monitor USB-C upstream port and I set the windows display settings to extend but the monitor always reports no signal detected but the devices do charge.

At the moment the common denominator appears to be a fault with my monitors. I’ve had no response from support yet though.

I have now tested a Macbook Pro 2018 Model using one of the thunderbolt 3 ports on the Macbook Pro to connect to my ES07D03 monitor USB-C input port. I am using an Intel Certified Maxonar Thunderbolt 4 cable

The MacBook Pro charges from the monitor and detects it only as capable of 4K30hz but the monitor displays no video.


If I then press the joystick on the back of the monitor to wake it from sleep the MacBook no longer detects it at all but still continues to charge.