Comment 32 for bug 219057

Hi everyone,

I had the same wifi/bluetooth interference problem. My setup is as follows:
- Ubuntu 14.04 with custom-built vanilla kernel 4.3.0
- Lenovo B50 laptop having QCA9565 / AR9565 Wireless Network Adapter (ath9k) onboard
- Linksys WRT-54GL router running DD-WRT v24-sp2 (10/10/09) mini
- Marshall Acton bluetooth speaker

Initially when I was streaming audio to the speaker, wifi degraded dramatically. After doing some research, I have successfully resolved the issue.

What I have done is:

* On my laptop:

- added
```
Enable=Source
Disable=Socket
AutoConnect=True
```
to /etc/bluetooth/audio.conf

- Added
```
options iwlwifi 11n_disable=1 bt_coex_active=1
```
to /etc/modprobe.d/iwlwifi.conf
However, since I'm not using iwlwifi, I'm not sure whether this had had any effect whatsoever.

* On my router:

- Under Wireless / Advanced Settings, I set "Bluetooth Coexistence Mode" to "Preemption"

Then I've rebooted everything just in case.

FYI, I encourage you to read through https://wireless.wiki.kernel.org/en/users/documentation/bluetooth-coexistence to find out what bluetooth coexistence is, and I wonder why everybody keeps switching it off (by setting bt_coex_active=0). On the contrary, this technique is designed to defeat interference problem.

Also, you may find nice to add "load-module module-switch-on-connect" to /etc/pulse/default.pa so that audio starts streaming to bluetooth speaker automatically when it connects (and then back to laptop speakers when it disconnects.)

Cheers,
PD.