Observations on USB 3.0/2.4GHz WiFi interference

Discussion in 'MacBook Pro' started by Aurora Wright, Dec 10, 2016.

  1. Aurora Wright macrumors member

    Aurora Wright

    Joined:
    Mar 3, 2016
    #1
    For anyone interested, I made some tests for the USB/WiFi interference.
    I kept the MacBook (a 15" model) connected to the 2.4GHz band of the router; physically close to it.
    The connection quality with no USB 3 connected devices was as follows:
    - RSSI: -50 dBm
    - Noise: -95 dBm

    Using this LAN adapter (top left port):
    - RSSI: -49 dBm
    - Noise: -75 dBm
    (2.4Ghz band is unusable, no webpages load)
    Top right port:
    - RSSI: -50 dBm
    - Noise: -72 dBm
    (OSX automatically reconnects to 5 GHz)
    Other ports also don't work.

    Using this USB-C hub (top left port):
    - RSSI: -51 dBm
    - Noise: -71 dBm
    (2.4Ghz band is unusable, no webpages load)
    Strangely enough, other ports work fine with this hub, with a Noise of -80 or so. So it would appear the top-left port is the most sensitive to interference.

    Using the Apple USB-C -> USB-A adapter and a Transcend USB 3 thumb drive (top left port):
    - RSSI: -52 dBm
    - Noise: -78 dBm
    (quite a bit of interference, but it doesn't disconnect)

    Top right port:
    - RSSI: -52 dBm
    - Noise: -84 dBm

    Using the official adapter and a USB 3.0 Toshiba Hard Drive I get no noticeable interference:
    - RSSI: -53 dBm
    - Noise: -92 dBm

    I'm pretty sure Apple cheaped out on the USB-C ports and didn't add (enough) shielding (does this happen with previous years models?).
     
  2. DanJBS macrumors member

    Joined:
    Aug 19, 2014
    Location:
    UK
    #2
    I have had issues with both the 15 and 13 " models. Was hoping that a software update can fix this. Strangely when I connect the usb-c usb 3 adaptor there is no interference, but when I plug in an external drive I lose internet completely. :(
     
  3. Aurora Wright thread starter macrumors member

    Aurora Wright

    Joined:
    Mar 3, 2016
    #3
    I don't think this is a software issue (I really hope I'm wrong though!). I also saw a YouTube video of one of those USB "thumb drives" which overpower the USB port and fry the internals of computers and other devices, and while it didn't work at all on 2015 and previous models (the ports had overcurrent protection), it works on the 2016 models; hence they probably cheaped out on the ports. This is the only annoying issue I found with this machine so far.
     
  4. Fishrrman macrumors G4

    Fishrrman

    Joined:
    Feb 20, 2009
    #4
    USB interference has nothing to do with software.
    It's all "in the hardware" ...
     
  5. npreq macrumors member

    npreq

    Joined:
    Nov 23, 2016
    #5
    Hey, are you by any chance the aurora from gbatemp? ;)
    Anyway, could you please repeat your test, but wrap your devices in aluminum foil, either encompassing the cable (if any) or just the end device?

    I've had a bunch of dongles and devices up to now - usb3 adapters, hdmi out, ethernet cards, and none of them caused any issue. That said, it can happen in 2 ways - the device itself doesn't use filtering on the data lines, or it leaks to ground which will wreak havoc on all of the laptop. If it works with the foil, then there's your answer. If not, then yeah, apple screwed up big time.
     
  6. DanJBS macrumors member

    Joined:
    Aug 19, 2014
    Location:
    UK
    #6
    I tried the foil and it worked. Also covering the cable with my hand seems to do the trick.
     
  7. Garage Battle macrumors member

    Joined:
    Aug 31, 2007
  8. jerryk macrumors 68030

    Joined:
    Nov 3, 2011
    Location:
    SF Bay Area
    #8
    Sounds like a number of 3rd party cables and devices have issues. This should not surprise anyone. There is a reason they price is cheaper. As they say, you get what you pay for.
     
  9. DanJBS macrumors member

    Joined:
    Aug 19, 2014
    Location:
    UK
    #9
    They were a bit cheaper than Apple accessories. I eventually went to the apple store and bought one there. Problem with it is not the price but the fact that they don't have one that supports displayport therefore I am stuck on 4k 30hz instead of 60hz. I guess that will do for a while until they release something else.

    This is the main problem with these macbooks. They don't have compatible accessories for sale.
     
  10. poorcody macrumors 6502

    poorcody

    Joined:
    Jul 23, 2013
    #10
    Thanks Aurora, that's interesting... so your tests show that the left-top port is the only "vulnerable" one? The WiFi antenna must be near there...

    My father has a similar problem with his Mac Mini (latest model). They really need to get the antenna farther away from the USB ports.
     
  11. jerryk macrumors 68030

    Joined:
    Nov 3, 2011
    Location:
    SF Bay Area
    #11
    That is the early adopter issue that has been around forever. And this one reason I usually wait a year to let the dust settle, drivers mature, and bugs get found, before upgrading to a system that has had many changes.
     

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