BCM4352 Bluetooth audio stutter

[Wurlitzer-1]

I'm close to having everything working on my laptop.
I installed the BCM94352HMB wifi/bt card, and everything seems to work, but listening to music on bluetooth headphones results in terrible audio stutter. Connecting to another bluetooth headset results in the same problem.

RehaMan, could you perhaps have a look at my configuration, and see if there aren't any blatant errors?
I believe I installed this card by the book, unless...

---
$ kextstat|grep -y acpiplat
13 2 0xffffff7f82e11000 0x66000 0x66000 com.apple.driver.AppleACPIPlatform (4.0) 3BE4E926-E063-3BBD-BE05-F6F97358C7A4 <12 11 7 6 5 4 3 1>

$ kextstat|grep -y appleintelcpu
outputs nothing

$ kextstat|grep -y applelpc
81 0 0xffffff7f82abb000 0x3000 0x3000 com.apple.driver.AppleLPC (3.1) 32BDCF9F-0473-32D4-9DAE-F523EFB2D244 <80 12 5 4 3>

$ sudo touch /System/Library/Extensions && sudo kextcache -u /
Password:
kext-dev-mode allowing invalid signature -67062 0xFFFFFFFFFFFEFA0A for kext BrcmPatchRAM2.kext
kext-dev-mode allowing invalid signature -67062 0xFFFFFFFFFFFEFA0A for kext BrcmFirmwareRepo.kext
kext-dev-mode allowing invalid signature -67030 0xFFFFFFFFFFFEFA2A for kext aDummyHDA.kext
kext-dev-mode allowing invalid signature -67061 0xFFFFFFFFFFFEFA0B for kext AirPortBrcm4360.kext

View attachment patchmatic-extract.zip
View attachment CLOVER.zip
View attachment wurlitzer-1.ioreg

 

[RehabMan]

I'm close to having everything working on my laptop.
I installed the BCM94352HMB wifi/bt card, and everything seems to work, but listening to music on bluetooth headphones results in terrible audio stutter. Connecting to another bluetooth headset results in the same problem.

RehaMan, could you perhaps have a look at my configuration, and see if there aren't any blatant errors?
I believe I installed this card by the book, unless...

---
$ kextstat|grep -y acpiplat
13 2 0xffffff7f82e11000 0x66000 0x66000 com.apple.driver.AppleACPIPlatform (4.0) 3BE4E926-E063-3BBD-BE05-F6F97358C7A4 <12 11 7 6 5 4 3 1>

$ kextstat|grep -y appleintelcpu
outputs nothing

$ kextstat|grep -y applelpc
81 0 0xffffff7f82abb000 0x3000 0x3000 com.apple.driver.AppleLPC (3.1) 32BDCF9F-0473-32D4-9DAE-F523EFB2D244 <80 12 5 4 3>

$ sudo touch /System/Library/Extensions && sudo kextcache -u /
Password:
kext-dev-mode allowing invalid signature -67062 0xFFFFFFFFFFFEFA0A for kext BrcmPatchRAM2.kext
kext-dev-mode allowing invalid signature -67062 0xFFFFFFFFFFFEFA0A for kext BrcmFirmwareRepo.kext
kext-dev-mode allowing invalid signature -67030 0xFFFFFFFFFFFEFA2A for kext aDummyHDA.kext
kext-dev-mode allowing invalid signature -67061 0xFFFFFFFFFFFEFA0B for kext AirPortBrcm4360.kext

View attachment 177989
View attachment 177990
View attachment 177991

AirPortBrcm4360.kext should not be patched. Restore to vanilla.

The FAQ has all BCM4352 requirements: http://www.tonymacx86.com/el-capita...faq-read-first-laptop-frequent-questions.html

Remove virtualbox.

BrcmPatchRAM is not up-to-date. You have 2.2.3. Current is 2.2.4.

Problem may be inherent in 13d3:3411 (from reports here, it does not have good compatibility).

 

[Wurlitzer-1]

I restored AirPortBrcm4360.kext to vanilla - can't believe I missed that.
Removed Virtualbox.

BrcmPatchRAM is not up-to-date. You have 2.2.3. Current is 2.2.4.

The BrcmPatchRAM2 in your bitbucket is still at 2.2.3?

Problem may be inherent in 13d3:3411 (from reports here, it does not have good compatibility).

Damn, I'm unlucky with this card. Second one I get.

 

[RehabMan]

The BrcmPatchRAM2 in your bitbucket is still at 2.2.3?

The latest can be built from sources. But the changes are probably not important.

 

[Wurlitzer-1]

The latest can be built from sources. But the changes are probably not important.

Alright. Thanks again for the help.
For the record, I just did a fresh install and this didn't solve my problem.
I'll go with a USB bluetooth module, or a new card (hopefully the right model) from ebay.

 

[Wurlitzer-1]

Hmm, seems the answers in this thread are helping a lot: http://apple.stackexchange.com/questions/167245/yosemite-bluetooth-audio-is-choppy-skips

I still get a stutter or two, but they are much more rare.

 

[Wurlitzer-1]

Update with workaround.

The fixes above didn't work at all – they increase the bluetooth buffer and it does help, but dropouts are still frequent. Connection with a bluetooth mouse was laggy as well.

However, connecting to 5Ghz wifi completely solves the issue. I have been testing for two days with no problem.

So it seems the problem was interference, as wifi and bluetooth both occupy a section of the 2.4 GHz ISM band. When not connected to wifi, OS X will scan for networks, and even that will interfere.

 

[RehabMan]

Update with workaround.

The fixes above didn't work at all – they increase the bluetooth buffer and it does help, but dropouts are still frequent. Connection with a bluetooth mouse was laggy as well.

However, connecting to 5Ghz wifi completely solves the issue. I have been testing for two days with no problem.

So it seems the problem was interference, as wifi and bluetooth both occupy a section of the 2.4 GHz ISM band. When not connected to wifi, OS X will scan for networks, and even that will interfere.

If you have to use 2.4 WiFi, it might help to change the channel used for the WiFi radio.

 

[Wurlitzer-1]

If you have to use 2.4 WiFi, it might help to change the channel used for the WiFi radio.

Tried them all... Dropouts occurred on all channels, but they had a different behaviour depending on the channel, i.e. the dropouts would occur only when uploading, or only when downloading.

 

[RehabMan]

Tried them all... Dropouts occurred on all channels, but they had a different behaviour depending on the channel, i.e. the dropouts would occur only when uploading, or only when downloading.

Hopefully you can just use 5Ghz.

My 2.4 Ghz WiFi is completely killed by the microwave in the kitchen...