4K output depends on computer connected

Hello,
I bought an av.io 4k to connect a 4k camera to a computer for video capture. I connected to my MacPro computer and it works great. I wrote a video capture SW and again it works great.
I ran my app on a MacBook Pro today and the video resolution is 1080p… Checking with the configuration tool shows the camera is outputting 4k. I did a bit of hunting and it seems the 4k re-scales output based on the connected recorder (my MacBook). Now my MacPro has 4k monitors connected but my MacBook has lower resolution.
Is there anyway to ether disable the re-scaling in the 4k?
or
does anyone know how to get a MacBook tell the 4k it can accept 4k?

The AV.io is seeing the signal as 4K in the configuration tool because it is indeed 4K. The scaling and output is entirely dependent on the third party software of choice. You will need to adjust the encoding settings, frame size and colour space in the software to output the desired 4K capture source in order to correct the behavior

So that was the second part of my question. How do you get OS-X to do that. There is no third party SW or application. The signal is being received directly with AVFramework using AVCaptureDeviceInput

AV.io series devices use the UVC libraries that are built into the operating system for functionality. The Config tool sees 4K which means that is the registered resolution being recognized correctly. If you are unable to request the 4K resolution in the application or platform you are using it’s possible it does not support the desired 4K request.
If the config tool was not recognizing the 4K signal then you could create a user mode in the configuration tool in order to try and prioritize the UHD resolution, however that is the extent of control and function from AV.io. The rest is entirely up to the host system and application. FFMPEG can certainly be utilized as well.