USB Hub Problem

Discussion in 'MacBook Pro' started by broadcast, Jul 17, 2012.

  1. broadcast macrumors member

    Apr 21, 2010
    I am having trouble with my USB hub, or should I say hubs.

    My first hub was not powered, but it worked fine until it randomly started cutting in and out. I figured that hub was broken, so I bought a new hub (unpowered) which worked fine for a while until it started doing the same thing. I thought maybe it was just another faulty hub, so I exchanged it and the same thing happened again.

    I decided to plug my original hub back in, and it worked fine for a while until it started cutting in and out again, and occasionally stop working all together. I replaced the cable, same thing happens. I went and bought a powered hub, same thing happens.

    I only have 3 devices plugged into my hub: a mouse, a set of speakers, and a printer. I've taken it to the Apple Store and the "Genius" tells me there's nothing physically wrong with the ports.

    I'm convinced it has to me my laptop because I've replaced the hub 3 times, tried a different mouse, tried different cables, and tried each port but it's still giving me the same problem. I've tried plugging in each device by itself into both the hub and directly into my laptop.

    Anyone have ANY suggestions? I'm stumped and fed up with spending money on USB hubs.

    My laptop is a 2010 Macbook Pro / 2.66GHz i7 / 8GB RAM / OS X 10.7.4
  2. Weaselboy Moderator


    Staff Member

    Jan 23, 2005
    It sounds like your combination of devices is drawing too much power for an unpowered hub and you need to upgrade to a powered hub.

    If you just run one device at a time, with the others unplugged from USB, does it work okay then?
  3. broadcast, Jul 17, 2012
    Last edited: Jul 17, 2012

    broadcast thread starter macrumors member

    Apr 21, 2010
    The 3rd hub I bought was powered and it still does the same thing.

    I've ran each device individually through the non powered hubs before too and it was doing the same thing, which makes me suspect it has something to do with the computer.

    Edit: The hubs will start working again if I unplug EVERYTHING from the hub and plug it back in again. Which means I have to unplug all 3 devices, the connection to my laptop, and the AC adapter, then plug it all back in. It'll stop working again once it wakes up from sleep. I'm 99.99% sure none of these hubs are faulty, since I tested it with another computer. I think it's something about the computer going to sleep that is causing it to not work and it's really confusing me.
  4. Jacobwilson99 macrumors member

    Jun 3, 2012
    I had the same problem for SO long! My HDDs would constantly be unmounting themselves.
    When the things plugged into hub lose connection, try pushing the cable going into your laptop up or down. Wiggle it and keep it in on place.
    What happened with mine: there was a little slouch with my FW800 port, so when the cable slouched down a little, the pins weren't fully connecting. I had to prop up the cable right next to the port to get all of the pins to connect.
    In my own experience, the cables and hub were not the problem. I have a 2007, 15" mbp, and the port on the MacBook are definitely my problem.
  5. imorton macrumors 6502

    Aug 21, 2010
    I think that the early 2011 13" MBpro has two differently powered ports.

    I find that if I plug my 10port Powered USB Hub on the "closer to the front" USB port, the 3 external HD's tend to disconnect.

    If I plug in the powered 10port USB Hub on the rear USB port on the Macbook Pro, my 3 external HD don't disconnect.

    Something tells me that the available power is not the same since the iSight camera is on one of the ports.

    I am open to other clues... IAN
  6. broadcast thread starter macrumors member

    Apr 21, 2010
    Yeah I believe the one in the back is powered, which is normally where I plug my bus powered external hard drive when I need to use it. I've tried both ports and they both do the same thing.

    But even with a powered hub it's cutting out, which is what is boggling my mind; especially since a mouse, a set of speakers (which aren't even bus powered, it has it's own power source) and a printer doesn't draw as much power as an external HDD to begin with.


    Actually sometimes when I don't plug the cable in all the way it will work fine for a while before cutting out again, which made me suspect the USB port itself is faulty... or it could have been a coincidence. This was my first trip to the Apple store, and the guy told me the port was fine.

    I forgot to mention I've reset the PRAM and SMC already. After having the same issue with 3 different hubs and numerous cables, I am out of ideas lol.
  7. imorton macrumors 6502

    Aug 21, 2010
    I agree, there is definitely something funky going on with the USB ports.

    If we look at the "about this Mac" and the "more info" and in the USB device tree section, we see more detailed info such as "Current Available & Current Required".

    I truly believe that both USB ports on the Macbook Pro are slightly different in regards to power available & required.

    Just my thoughts, but I am open to new facts... :)

  8. broadcast, Jul 23, 2012
    Last edited: Jul 23, 2012

    broadcast thread starter macrumors member

    Apr 21, 2010
    It worked for another week and now it stopped working. It worked for a bit when I wiggled it and pushed it down, so either the port is bad or the cable. I replaced the cable and it's the same thing. I seriously suspect it's the port.

    I might have to make another trip down to the Apple store because I am beyond fed up with such a simple problem. I won't leave until they do more than just shine a flash light into the port and say "yep, looks fine."

    Edit: Just plugged my old unpowered hub in and it works like a charm. All 3 of my hubs, powered or unpowered will randomly choose when they want to work. I am sooooo baffled by this.

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