Mouse and application lag on external monitor

I am currently using a late 2015 macbook pro on an external 4k monitor. I am having issues lately with mouse lag and using different applications like music and and safari. For example when opening Safari the app opens much slower and when changing tabs it doesn't happen right away. While on Safari there has also been issues that websites do not load fully and I have to refresh the page multiple times. An example of this would be for example on Amazon when I enter the website, I am unable to search or click something as the screen is still loading or frozen. Another issue I am having is when I minimize Safari and click on it again, it will take awhile/lag to open again.


The MacBook is connected to the monitor using an HDMI cable. Below will be specifications of my MacBook and Monitor.


If there is any information or steps i need to fix this issue? I have already reset the NVRAM and SMC but those have not helped.


Macbook Pro:

MacBook Pro (Retina, 13-inch, Early 2015)

Processor 2.7 GHz Dual-Core Intel Core i5

Memory 8 GB 1867 MHz DDR3

Graphics Intel Iris Graphics 6100 1536 MB


External Monitor:

LG 32uk550

Posted on Jan 27, 2021 6:05 PM

Reply
3 replies

Jan 30, 2021 1:17 PM in response to edgar_manoukian

Hi Edgar,


We understand you're experiencing some problems with your MacBook Pro, and we'd like to help. So we're on the same page, do these behaviors only happen when the external display is connected? If so, are you able to try connecting to a different Wi-Fi network or using an Ethernet cable from the Mac directly to the router to see if the behavior continues? When the Mac stops responding, what do you see in Activity Monitor? This will help us isolate the problem a little more.


View information about Mac processes in Activity Monitor


Please let us know what you find.


Thanks!

Feb 20, 2021 2:42 PM in response to edgar_manoukian

Hi Edgar,


Thanks for following back up with us! From what you're describing, it sounds like the lag could be caused by the external display, but we'd like to do a little more troubleshooting to confirm. Which version of macOS is currently installed? The reason we ask is that Activity Monitor is included as part of macOS, and shouldn't need to be downloaded from the App Store. Were you also able to test theWi-Fi with a different network connection? If your network uses a multi-band router, testing could also be done by moving the connection from the 2.4 GHz network to the 5 GHz.


If the issue persists on both networks, it's also recommended to try starting the MacBook Pro up in safe mode. This will disable a lot of third-party software, and determine if the issue is caused by macOS or another source.


How to use safe mode on your Mac


Have a great day!

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Mouse and application lag on external monitor

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