HDMI TV as 2nd display causes mouse stuttering when TV turned off

Question

HDMI TV as 2nd display causes mouse stuttering when TV turned off

I have a 2014 Mac Mini. The main display is 27" Cinema Display. I've hooked up to my TV as secodary display, using the mini's HDMI port.

All is well when the TV is on. But when I turn the TV off, the mouse pointer stutters / hangs every couple of seconds, making my Mac pretty much unusable.

So currently having to keep the TV on permanently, which is not great for my electric bill, or the environment.

Any workarounds? Short of pulling the HDMI plug out every time I don't want to use the TV as second display.

I can't see anything in Display Preferences that will allow me to "ignore" the HDMI device when I want to.

Nothing shows up in Activity Monitor, there is no CPU burst or anything. What is OSX doing that stops the mouse from working every couple of seconds?

Mac mini, macOS High Sierra (10.13.3), Late 2014 Model

Posted on Apr 4, 2018 9:21 PM

Reply

Answer 1

MoonJ.

Community Specialist

Apr 5, 2018 1:49 PM in response to sadasdadadasdsa

Hey sadasdadadasdsa,

I understand you're having an issue with your mouse lagging when your TV is connected but not powered on as your second display. I'd love to help isolate what's going on with you.

First, let's try testing with another HDMI cable. This can help us determine if the HDMI connection is the issue.

After that, I'd like for us to reset the SMC and NVRAM on your Mac mini:

How to reset the System Management Controller (SMC) on your Mac - Apple Support

How to reset NVRAM on your Mac - Apple Support

Let me know how that goes!

Thanks!

Reply

Answer 2

Apr 6, 2018 12:48 AM in response to MoonJ.

Thanks for the reply. Unfortunately it's the only HDMI cable I have, so can't test with another one. It's also 3M long and needs to be to get from Mac to TV, so it's not the sort of thing other people have hanging around.

I'm not doing all that system and NVRAM reset stuff, purely on the basis my machine is only 3 weeks old. So I very doubt that is the issue. And it seems to be mentioned as a "cure all" for Mac problems with no known solutions.

I do have one correction from my first post:

I can confirm pulling the HDMI cable from the TV solves the issue, as does turning the TV off completely, rather than having it in standby. It's just when TV is in standby mode the issue happens.

So it's something in how OSX deals (badly) with my HDMI TV when it's in standby mode. Standby mode obviously means the device is powered and connected, but OSX can't deal with the fact it won't display anything or presumably respond to commands.

If there is no solution, I'll simply turn the TV off properly, instead of leaving it in standby mode all the time 🙂

Reply

HDMI TV as 2nd display causes mouse stuttering when TV turned off

Similar questions