MBP 2019 (Intel+AMD) + native smooth scaling - loss of video signal

[laxu]

I wanted to add more scaling options to my 4K Samsung G70A display so I set the options in BetterDisplay settings to let BetterDisplay control it.

After restarting my Macbook Pro 2019 Intel 16" w/ Radeon 5300M, I can no longer get display output from either of the left side ports on the computer. I can get output when I plug the display into the right side ports that I wasn't using when I set those BetterDisplay settings.

I did all the steps here: #191 but that did not restore the functionality. The display simply does not get detected on the left side ports and goes back to sleep. Does not matter if BetterDisplay is running or not.

Using either DP or HDMI with USB-C adapters for the port type gives no image if on the left side ports. USB still works on the left side ports, video output does not.

I am using the paid Pro version.

Is there something I still need to remove or did BetterDisplay somehow manage to mess up the ports on my MBP?

[laxu]

I even tried with a cheap 1080p display using HDMI and I can only get display output from the right side ports.

[laxu]

Ok I fixed this by shutting the computer down and then resetting SMC as per https://support.apple.com/en-us/HT201295

[laxu]

Reopening, it seems the above did not work and this issue was caused again as I tried to enable the features on BetterDisplay.

[waydabber]

Thanks for the info and glad it sorted out.

To be honest I don't see how BetterDisplay can actually mess ports up (there is nothing port dependent in what the app is doing), so it might have been a freak coincidence. But if you can reproduce the issue, there might be something I am not aware of. What settings exactly did you try to change? Maybe understanding this might shed some light on the problem.

Thank you!

[laxu]

I only tried to enable the smooth scaling options from the settings. Have been able to get this happening twice so far,

[waydabber]

I see. If you turn this off and disable configuration editing, does the issue resolve itself? The changes this function do does not affect specific ports directly, but alters some of the system configuration files - these should affect the display with the given vendor/model ID. There is no clear reason why the left ports should be affected and not the right ports. However macs try to remember the specific resolution options set by the user and apply it during startup. It might be possible that this somehow does not work well with the 2019 Intel+AMD MBP (among several other things, this mac is an outlier in many respects and a lot of other stuff do not work or work differently or unexpected ways on this model).

[waydabber]

so what you should try doing is this:

1. Remove the custom configuration:

• Navigate to your computer's /Library/Displays/Contents/Resources/Overrides folder and remove all folders and files.

2. Reset BetterDisplay (while it is not running):

• Open Terminal and run the following command: defaults delete me.waydabber.BetterDummy (note: it is not BetterDisplay, but BetterDummy)

3. Remove the display configuration files:

• Navigate to your computer's /Library/Preferences folder in Finder and remove the file com.apple.windowserver.displays.plist
• Navigate to your user's ~/Library/Preferences/ByHost folder in Finder and remove every file that starts with com.apple.windowserver

After this point be careful not to alter the display configuration in any way but reboot and perform an NVRAM (I don't think an SMC reset is needed as on Intel mac screen resolutions are stored in the NVRAM). This should safely delete any boot related info regarding screen resolutions.

These steps should clear any residual effect of the configuration changes. If smooth scaling does not work properly, you might want to try setting some custom resolutions and see if that works properly.

Let me know if this helps!

[laxu]

Thanks, I tried these and after that reset both NVRAM and SMC but even creating a new account on the computer it doesn't seem to solve it. Right side works, left side does not.

Maybe this is just a fluke and my ports are simply busted.

I agree that the app itself should not be able to cause this and then should not have an effect on other displays either. If I connect to the right side then it seems to be detected as another display or the BetterDisplay settings at least don't apply, no smooth scaling etc.

However your app does have a specific issue: If it cannot detect the display, you cannot remove the configuration without going through the steps you mention above as the display is no longer visible in the app. I think it would be good if it could keep a list of devices where you have enabled these configurations so it's easy to revert the changes and solve the problem.

Having a feature to perform the above tasks at the push of a button directly from the app would also be appropriate.

[waydabber]

Is it only displays that affected or every USB-C connection?

I agree, a feature to remove the configuration for disconnected displays would be appropriate (this would require a more substantial change however so disconnected displays are accessible, which requires storing all the details of these displays that allow presentation - this is currently not done, only identifiers are retained - this change would work only going forward). I'll add an enhancement regarding this.