usb-c adapter + lag issues.

Discussion in 'MacBook' started by bobtheknight, Jun 4, 2015.

  1. bobtheknight macrumors newbie

    Jun 4, 2015
    Hi all, picked up the base rMB today, coming from a late 2013 rmbp (rmbp is amazing, but just a tad heavy when I travel). Anyway I also picked up the USB-C digital av multiport adapter and at work - connected the rMB to a 1920x1080 external 27inch monitor via HDMI, the usb port connected to the wireless dongle of a wireless mouse/keyboard, and of course the power was connected to the power. So all 3 sockets of the USB-C adapter were used up at the SAME time.

    Man is there lag!. I don't know whether its the bandwidth of the USB-C (it had to run a display AND cater for the mouse/keyboard via USB), but the mouse cursor had massive stutter, scrolling on safari and chrome was slow. It really was bad. I only use MS Office and Chrome.

    I had a first generation MBA 11inch (2gb ram only) and can remember it was a much smoother experience with a similar external monitor setup, perhaps because of the external graphics card. I really didn't expect a 2015 machine to be this slow on the most basic programs.

    Hope there is a fix soon from Apple or if anyone has any ideas....
  2. keviig, Jun 4, 2015
    Last edited: Jun 4, 2015

    keviig macrumors 6502

    Jun 7, 2012
    I use my rMB in a similar setup, just connected to a 1080p TV instead. While there is some lag, it really isn't much worse than it is when it's not connected to anything. The USB c bandwidth shouldn't be a problem. Keyboard/mouse barely uses any bandwidth at all.

    Double check that your output to the external monitor is set to 60 hz. I had to plug the HDMI cable into a dedicated "PC HDMI" input on my TV to get 60 hz.
  3. tutux macrumors member


    May 4, 2015
    For sure nothing to do with the screen-USB bandwidth as the USB will use UNUSED pins of the USB connector to send the video.
  4. bobtheknight thread starter macrumors newbie

    Jun 4, 2015
    its noticeable to the extend that it becomes unusable/annoying. My colleague came over to show me a website, she started scrolling with the mouse wheel and the page would stutter along. Then I updated an excel and the mouse cursor would be so slow and text would be slow to update. The effect is like there isn't enough RAM, which isn't true of course. I really don't think its a the spec config, although Im not sure about the Intel processor being listed only as 1.1Ghz, but the thing has 8gb of ram!.

    Its not like its that slow all the time. Its normal for 30 secs, then lags like crazy, almost like a personality disorder ;)

    My point is that if the first gen mba 11inch didn't have these problems how come we have it today? Apple must realise a majority of rMB buyers would be [business] users who would connect to an external monitor whilst in office.

    [I have since read about the transparency workaround, and will try that tomorrow]
  5. keviig macrumors 6502

    Jun 7, 2012
    It seems to be a problem with all retina macbooks. My 2012 15" rMBP and the 2015 13" rMBP i had earlier showed the same behaviour.
  6. bobtheknight thread starter macrumors newbie

    Jun 4, 2015
    actually both my first gen mba 11, and rmbp late 2013 were fine and did not show this behaviour. I have connected all my laptops at work to 1080p displays. None have stuttered as badly as the current rMB. Anyway I have spent less than 24 hours with it, lets see what happens going forward. I will take my imac's bluetooth keyboard and mouse in tomorrow to see if there is any difference over the logitech usb wireless mouse/keyboard.
  7. fatefulwhisper macrumors regular

    Jul 24, 2008
    No lag here... I've have the 1.2/512 model rMB, and I actually own two Multiport AV adapters (one for work, one for home), and have had my rMB + 2 adapters for about 6 weeks now. I use them all everyday, both connected to the same type of monitor (27" Dell U2713HM), using HDMI->DVI at 1440p resolution. As a developer, I need the extra screen real estate for coding, so I take advantage of that everyday. I also plug in the usb port to my Dell's monitor (as it has a 4-port USB hub), and I have things such as hard drives and my iPhone connected to it on a daily basis.

    The apps I run all the time:
    Chrome Canary (fixes a lot of Chrome related battery and lag issues)
    Sublime Text 3
    Vagrant/VirtualBox running Debian Linux w/ 512MB ram
    VMWare Fusion running Windows 8.1 w/ 4GB of ram
    Plus about a dozen other apps, which use little or no resources (terminal, itunes, messages, etc.)

    Apps I run occasionally:
    Microsoft Word & Excel
    Adobe Photoshop

    I experience no lag, and I have transparency on.
  8. bobtheknight thread starter macrumors newbie

    Jun 4, 2015
    Glad to hear this, I connect HDMI ---> HDMI, I'm on 1920x1080
    what keyboard/mouse combo do you use? bluetooth or USB wireless.
    As for programs I only use MS PS, nothing taxing whatsoever...
  9. fatefulwhisper macrumors regular

    Jul 24, 2008
    I did HDMI->HDMI the first week I had the laptop because I didn't have a DVI adapter yet; and it looked pretty horrible on my DELL (1080p was not native resolution), but again, zero lag issues, even on 1080p (well I run at a much higher resolution now, so no surprise there).

    I use Apple's bluetooth wireless keyboard and trackpad.

    I try to tax the CPU as much as I can :) I'm always trying to push the limits of the machine everyday and usually come out surprised in the end. The only thing that consistently lags for me are 3d games on super high settings of course.
  10. bobtheknight thread starter macrumors newbie

    Jun 4, 2015
    Ok, I found the problem, its the [logitech] mouse and keyboard combo VIA A WIRELESS DONGLE CONNECTED TO USB OF THE MULTIPORT ADAPTER. sorry for the caps but its important.

    The slowdown or "lag" seems to be the signal from the logitech mouse/keyboard - cannot be processed quick enough so it looks like "lag". I know this as I compared with the Apple keyboard/mouse (CONNECTED VIA BLUETOOTH), and it has none of the "lag" issues.

    so bluetooth vs wireless dongle (via USB)...thats the issue.

    Never had this problem with my old macs connected via the usb wireless dongle.

    Anyone else have this issue?
  11. strevat macrumors newbie

    Jul 5, 2017
    I'm suffering from exactly this right now. Any hint as to how you dealt with it?
  12. Yonge, Jul 15, 2017
    Last edited: Jul 15, 2017

    Yonge macrumors newbie

    Jun 15, 2017
    Do you notice the lag also in regards to the keyboard or just in regards to the mouse? What is/are the model of the logitech product/s?

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