Mac Pro 5.1 BT4.0 intermittently disconnecting

LEOMODE

macrumors regular
Original poster
Jun 14, 2009
242
9
Southern California
I installed a BT 4.0 adapter (BCM94360CD) fully internally within the Mac Pro.
Everything supports well (both in Boot Camp and Mac OS) as well as Continuity (El Capitan).

The only problem is its not smooth. I have other laptops with BT4.0 capability and they work just fine on my desk. (my Mac Pro is just underneath my desk to the right). I am using Logitech MX Master and Bose Soundlink Mini. They keep getting disconnected every 5 seconds or so and it's really annoying.

The only thing that blocks between my BT4.0 mouse/speaker and Mac Pro are pc speakers, wifi HP printer, Samsung monitor and Nvidia Shield. I turned off their Wifi as well but it's not any better.

It looks like the only way for me to get my mouse/speaker working without any disconnection is by putting them right next to where the BT adapter is (on the bottom of my Mac Pro). But it shouldn't be like this.

Would this adapter be faulty? I bought this on eBay but I want to know if I should've gotten an OSX Wifi model or something. I mean they should be the same thing. Or is there any app that I can check the BT signal to find out what/where my signal is getting killed?

Thanks..
 

h9826790

macrumors G5
Apr 3, 2014
12,766
5,577
Hong Kong
The problem is not the card, but the antenna.

It's a known problem that the Mac Pro's metal case somehow "block" the BT signal. You can go to Apple website and download BT explorer from the developer page (100% free). Use that to monitor the BT signal. You should see something like this.

54dB 100% LQ crop.jpg


For me, the BT usually works well, but when I switch on my scanner's Wi-Fi (2.4GHz only with a fixed channel). I can clearly see the the mouse connection quality drops a lot. And occasionally have "jumping" pointer. To avoid that, I bought a 3m long ipx -> SMA cable (about $1), and connect a 2.4GHz antenna (another $1) onto it. Put that antenna to somewhere near my mouse but I can't see it. I know it's not "internal" anymore, but there are lots of cable coming out from the back anyway, so why not add an extra cable that can fix the BT signal problem?

6.jpg
ANRD245X05-RSP-2013_Detailed.jpg


If you don't want this kind of antenna, and prefer everything "internal", you may buy a ipx -> notebook type antenna, connect that to the card, leave the antenna somewhere inside the Mac Pro's case, and hopefully that one can work as good as your laptop.
10PCS-LOT-font-b-WIFI-b-font-2-4G-3dbi-PCB-font-b-Antenna-b-font.jpg


Be careful don't buy the wrong cable. The card that on you Mac Pro should be using ipx 1 connector. Quite a few notebook using ipx 4 connector (smaller). If you go for the SMA route, make sure you pick the antenna that fit your cable (the pin can be on male / female side, so be careful to get the right combination).
 
Last edited:

LEOMODE

macrumors regular
Original poster
Jun 14, 2009
242
9
Southern California
The problem is not the card, but the antenna.

It's a known problem that the Mac Pro's metal case somehow "block" the BT signal. You can go to Apple website and download BT explorer from the developer page (100% free). Use that to monitor the BT signal. You should see something like this.

View attachment 681548

For me, the BT usually works well, but when I switch on my scanner's Wi-Fi (2.4GHz only with a fixed channel). I can clearly see the the mouse connection quality drops a lot. And occasionally have "jumping" pointer. To avoid that, I bought a 3m long ipx -> SMA cable (about $1), and connect a 2.4GHz antenna (another $1) onto it. Put that antenna to somewhere near my mouse but I can't see it. I know it's not "internal" anymore, but there are lots of cable coming out from the back anyway, so why not add an extra cable that can fix the BT signal problem?

View attachment 681549 View attachment 681550

If you don't want this kind of antenna, and prefer everything "internal", you may buy a ipx -> notebook type antenna, connect that to the card, leave the antenna somewhere inside the Mac Pro's case, and hopefully that one can work as good as your laptop.
View attachment 681551

Be careful don't buy the wrong cable. The card that on you Mac Pro should be using ipx 1 connector. Quite a few notebook using ipx 4 connector (smaller). If you go for the SMA route, make sure you pick the antenna that fit your cable (the pin can be on male / female side, so be careful to get the right combination).
Hey this is really helpful, thank you so much for your help. Let me look for your solutions and see how it turns out. You just saved me another $100 to buy another adapter.
 

ActionableMango

macrumors G3
Sep 21, 2010
9,263
6,249
The first thing I did was check your signature for a USB 3.0 card, and sure enough, there it was. USB 3.0 cards interfere with BT. Intel has a white paper about this here.

This happens even in stock configurations, like a Mac Mini with native USB 3.0 and BT--here is a thread about their problems. OWC even sells a shielding kit for the Mac Mini.

Because it is an interference issue, anything you can do to reduce the interference (such as shielding) or increase the reception of bluetooth (such as the suggested external antenna) is helpful. It is also helpful to unplug USB 3.0 devices when not actively using them, because the issue is most prominent when the card is communicating with a drive.
 
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LEOMODE

macrumors regular
Original poster
Jun 14, 2009
242
9
Southern California
The first thing I did was check your signature for a USB 3.0 card, and sure enough, there it was. USB 3.0 cards interfere with BT. Intel has a white paper about this here.

This happens even in stock configurations, like a Mac Mini with native USB 3.0 and BT--here is a thread about their problems. OWC even sells a shielding kit for the Mac Mini.

Because it is an interference issue, anything you can do to reduce the interference (such as shielding) or increase the reception of bluetooth (such as the suggested external antenna) is helpful. It is also helpful to unplug USB 3.0 devices when not actively using them. as the issue is most prominent when the card is communicating with a drive.
Oh my goodness. After removing the USB 3 out from the ports and not using them (yes I bought a separate USB3.0 hub that goes right into one of my PCIE slots so I can utilize more USB's), BT is perfect!!! (at least so far). Let me test it out for a few more minutes!!! Thanks so much!!!

Update: For about 30minutes, it is perfect. BT speakers work without any disconnect, and the mouse too!!! Thanks so much! After I reconnected the USB3.0 they are actually fine right now for some reason. Hmm so I don't know! But at least right now this has been a state where it had 0 disconnects so far.
 
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LEOMODE

macrumors regular
Original poster
Jun 14, 2009
242
9
Southern California
The first thing I did was check your signature for a USB 3.0 card, and sure enough, there it was. USB 3.0 cards interfere with BT. Intel has a white paper about this here.

This happens even in stock configurations, like a Mac Mini with native USB 3.0 and BT--here is a thread about their problems. OWC even sells a shielding kit for the Mac Mini.

Because it is an interference issue, anything you can do to reduce the interference (such as shielding) or increase the reception of bluetooth (such as the suggested external antenna) is helpful. It is also helpful to unplug USB 3.0 devices when not actively using them, because the issue is most prominent when the card is communicating with a drive.
Ok, so an update.

Actually after rebooting the computer, the problem persists again even without disconnecting the entire USB 3.0 ports.
Should I just try to take the USB3.0 PCIE card and try again as it should have some power on it while the computer is on?
 

ActionableMango

macrumors G3
Sep 21, 2010
9,263
6,249
Ok, so an update.

Actually after rebooting the computer, the problem persists again even without disconnecting the entire USB 3.0 ports.
Should I just try to take the USB3.0 PCIE card and try again as it should have some power on it while the computer is on?
You could try removing the card, but I don't remember anyone else having the problem when there weren't any devices connected. But then you won't have USB 3.0.

Personally I'd stick with a more permanent solution like the antenna suggested above.

Some people have adding shielding:
http://forums.macrumors.com/threads/usb-3-x-pcie-cards-for-classic-mac-pro.1501482/page-60#post-21591593

Some say that better cards have better shielding or design:
http://forums.macrumors.com/threads/usb-3-x-pcie-cards-for-classic-mac-pro.1501482/page-44#post-20232887

You can also try switching around the antennas. IIRC, many of the Mac Pros had the antennas installed incorrectly from the factory, such that the wrong antennas were being used, and thus making both wi-fi and BT reception terrible. There is a thread about that, but I cannot find it.
 

UKenGB

macrumors member
Feb 21, 2010
81
8
Surrey, UK
I have had this problem since I first bought my cMP 4,1. I had serious mouse connection issues even though the Magic Mouse was only about 3 feet from the nearest point of the Mac. In addition I wanted better range for a BT headset and to get around this incomprehensible (and reprehensible) situation Apple have created, I added an external antenna as I now see shown above.

I have just installed a replacement combi BT 802.11/ac card and forgetting how bad the problem was and no longer requiring a headset, I removed my external antenna and on starting up with the new card was surprised and horrified to find my Magic Mouse is unusable at 3ft. If I was left handed it would (just) work at 2ft. But I’m not. How can Apple make claims about this Mac having BT, when even just a mouse is unusable. Anyway...

I am now going to have to re-install my external antenna, however a quick question for any electronic gurus out there:-

Is the cable shield of the antenna connections simply chassis ground?

I previously had the SMA connector just dangling loose out the back. This was never actually a problem, but I’d like to tidy it by mounting the connector to the Mac’s case. This would ground the antenna’s shield, but they are likely to be grounded internally anyway. Or are they actually all isolated from ground?

Anyone know for sure?
 
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