I was previously using a Sony HWS-BTA2W bluetooth adapter from 2007 to get sound wirelessly from my computer or phone to a set of non-bluetooth speakers. It had a problem that only happened with my linux computer. I was annoyed with this device because as the workload would increase/decrease on my computer, the audio would speed up and slow down. You could hear the pitch rise and fall if you were listening to music. This is probably by design – as part of the base level Bluetooth SBC codec that everything supports. It makes sense that if you’re talking on the phone you’d want to hear everything someone said, even if it had to be sped up or slowed down for continuity.

The pitch bend happened on all of my linux laptops: 2008 Dell Studio 17 and my 2014 ThinkPad T440s, and my 2019 Developer Edition XPS 13. I wasn’t sure about the problem being in the linux bluetooth stack or the Sony device itself. I knew there was a better solution available – and it happened to be a combination of hardware and software.

After reading all about Bluetooth codecs and wanting another way to tap into my audio interface, I decided to try another, more modern, bluetooth interface. I went with a 1Mii B06S Bluetooth 5.2 Receiver. It supports several aptX profiles, which provide higher fidelity than the base BT codecs.

Interestingly, aptX originated as a PhD thesis, then later became incarnate in a DSP chip. Then the tech changed hands though several companies (including Solid State Logic which makes my audio interface). Before finally becoming part of Qualcomm. AptX was first used in the Bluetooth stack with some Sennheiser headphones from 2009. My 2007 Sony hardware was definitely not using this tech.

AptX on Ubuntu 22.04

To make sure my computer supported these extra codecs, I had to install some extras. Partly because aptX has some patent issues (although it’s been reverse engineered), and partly because I upgraded my system to use pipewire. The best source I found was this gist:

Enable PipeWire on Ubuntu 22.04

This guide is only for original Ubuntu out-of-the-box packages. If you have added a custom PPA like pipewire-debian, you might get into conflicts.

Ubuntu 22.04 has PipeWire partially installed and enabled as it’s used by browsers (WebRTC) for recoding the screeen under Wayland. We can enable remaining parts and use PipeWire for audio and Bluetooth instead of PulseAudio.

Starting from WirePlumber version 0.4.8 automatic Bluetooth profile switching (e.g. switching from A2DP to HSP/HFP when an application needs microphone access) is supported. Jammy (22.04) repos provide exactly version 0.4.8. So, we’re good.

Based on Debian Wiki, but simplified for Ubuntu 22.04.

Install

Install WirePlumber as the session manager:

$ sudo apt install pipewire-media-session- wireplumber

Notice ‘-‘ at the end of ‘pipewire-media-session’. This is to remove it in the same command, because ‘wireplumber’ will be used instead.

Start WirePlumber for your user:

$ systemctl --user --now enable wireplumber.service

Configure

ALSA

Install the ALSA plug-in:

$ sudo apt install pipewire-audio-client-libraries

And copy the config file from PipeWire docs (provided by the plug-in) into the ALSA configuration directory:

$ sudo cp /usr/share/doc/pipewire/examples/alsa.conf.d/99-pipewire-default.conf /etc/alsa/conf.d/

Check if you have other (like Pulse) configs in the /etc/alsa/conf.d/ installed by something else. You might want to remove them.

PulseAudio

Everything was done automatically by pipewire-pulse package, which should have been installed by wireplumber package as recommended. If not, install it yourself.

Bluetooth

Install the codecs and remove Bluetooth from PulseAudio, so it would be handled directly by PipeWire:

$ sudo apt install libldacbt-{abr,enc}2 libspa-0.2-bluetooth pulseaudio-module-bluetooth-

The supported codecs are SBC and LDAC.

Unfortunately, aptX and AAC are not supported because of patents and other technical reasons. aptX is available starting from 22.10 via libfreeaptx0 installed by default there (22.10 uses PipeWire by default as well). If you really need these codecs in 22.04 you may use this PPA from @aglasgall which is based on universe, but rebuilds pipewire with additional packages for aptX and AAC from multiverse. Read the discussion here.

Done

Reboot and check if it works by running:

$ LANG=C pactl info | grep '^Server Name'

view raw pipewire.md hosted with ❤ by GitHub

The important part in there is actually the link to the pipewire-extra-bt-codecs PPA for Ubuntu 22.04. I installed/removed the packages as expected and when I connected to the 1Mii B06S I can choose from all of the supported codecs in my sound settings:

I’m going to keep it on aptX HD for now and see how it sounds, but so far I’ve experienced zero pitch changes while listening to music.

Coming soon..

Next I’ll go through how I have everything hooked up in my home audio studio.

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This is just my experience, YMMV as they say…

In April of 2022 my VOIP home phone stopped receiving incoming calls. I could still dial out, but nobody could call the house. I received warning emails from Skyetel every 3 hours that my SIP endpoint was unreachable by their servers.

Since nothing had changed on my end, I suspected that something changed with my provider: Comcast/xfinity. Similar to my experience with British Airways, I found that xfinity has now automated everything.

I understand that automation helps if someone just needs to reboot their router, or forgot their wifi password. But for those who need genuine help getting shit done, it presents a huge barrier. It took me 9 calls and 3 trips to the xfinity store to get this resolved…

Continue reading →

Approach 1 (trying to fix the problem directly)

I phoned tech support to explain that port 5060 (for SIP service) was being blocked on my connection.

The first guy I talked to said they won’t open up that port unless I subscribe to xfinity’s VOIP service. Honestly, I didn’t want to talk to this guy anymore. He was obviously from India. No offense, but he sounded more like a scammer than a helper. I wanted to talk to someone who actually works for xfinity in the US, that actually knows how their network is set up. Before I hung up I got the phone number for Advanced Technical Support. It’s 888-780-8571. You’re welcome.

I called that number and magically wound up speaking with an actual technical rep based in these United States. BTW, this won’t happen every time – I’ve yet to figure out what automation magic I did to skip past the overseas nonsense.

When I mentioned my issue he referenced this page https://www.xfinity.com/support/articles/list-of-blocked-ports which I had also been looking at, noting that port 5060 isn’t in the list. He said I might need to do some configuration in my modem’s settings to forward that port.

But the Netgear CM1000 isn’t a combo modem/router. It doesn’t have a firewall or port forwards or anything. It just passes all connections on to my OpenWRT router which has firewall/forwarding/wifi/etc.

So the tech guy suggested I try an xfinity-supplied cable modem (at a rental fee of $15/mo) to see if that solves the problem. I wasn’t thrilled with the extra cost, but he said it’s pro-rated and might be worth seeing if it fixes the problem.

Approach 2 (playing the game)

So I went into my nearest xfinity store, went home with a new cable modem, and set it up. Then, to my dismay, when I went into the port forwarding settings on the modem, I consistently got this error:

I called technical support back and they said:

You need to go back to the xfinity store and get a different modem that is supported by the xfinity app. I’ve made a note on your account so they’ll give you the correct one this time.

WTF. OK, so I went back and returned my modem for another one. The new one worked with the app. I did have to do some weird things like disable IPv6 on my router so that it would show up in the xfinity app as an available device and port-forward destination because xfinity only supports port forwards via IPv4.

What’s really going on?

After configuring the router and updating my IP at Skyetel, it seemed to work 💪 Our home phone now rings after dialing. I called xfinity tech support again to re-activate my Netgear CM1000 to see if it will continue to work. Hey – it worked… But why?

My hunch is that by selecting a port forward in the app, something else is getting configured in their network to allow incoming connections – something upstream from your rental router. We’ll see how long the setting lasts before I have to go (temporarily) rent one again 🤞 Also – I was able to reactivate IPv6 in my router without issue.

The next day, the phone rang and it was music to my ears! ☎️ It was my daughter’s friend and they made plans to get together. Then the day after that, I received my first spam call 😱

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Holy 💩 y’all – I just spent two weeks not being able to share my screen on Ubuntu. It started with a regular system update that I think updated Wayland. I noticed that my fonts in certain applications looked sharper – likely meaning that the 4k scaling was working better. Then I noticed that zoom wouldn’t share the whole screen, it would just share a portion. 😩

To be clear about my setup, I was running Ubuntu 20.04 LTS with a dual monitor setup. I had been using Wayland because my XPS built-in screen is 4k and my external is standard HD (1080p).

As luck would have it, Ubuntu 22.04 LTS was recently in my update queue, and I figured it couldn’t get much worse. So I upgraded, but (womp womp) it didn’t help.

Continue reading →

Now zoom wouldn’t show a normal screen sharing option, but it had a new “System Capture” selection.

The system capture selection would bring up another new prompt:

But after I clicked “Share” nothing would happen. People on the other end would just see a black screen.

PipeWire Debugging

After some research it seems that the new sharing subsystem for Wayland is called PipeWire. In my quest to debug it end-to-end I found this handy guide for debugging screen sharing in Wayland, the “It doesn’t work” Troubleshooting Checklist.

One of the steps is to check the pipewire service itself:

systemctl --user status pipewire

And mine was up-and-running but was returning this warning in yellow:

no modules loaded

That led me to this post: https://www.linuxquestions.org/questions/slackware-14/using-pipewire-instead-of-pulseaudio-in-slackware-15-a-4175693980/page9.html

Yes it was for a different distro (Slackware) but one of the pieces of advice seemed sound:

Long story short, remove every little file from /etc/pipewire if exists and reboot the system.

I’m not sure why the folder was there with an old config file in it. Likely from when I was on 20.04 and tried upgrading PipeWire to try to fix zoom (which didn’t work).

I deleted that folder (actually moved it to a temporary place first), rebooted and it did the trick. Screen sharing is back on! Good thing because my job depends on it 💪

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Dude… you’re getting a Dell(?)!

The last 4 laptops I’ve owned went like this:

2004 – ThinkPad
2009 – Dell
2014 – ThinkPad
2019 – Dell

Whenever I had the Dells I would tell my wife: “Remind me to get a ThinkPad next time.” I wish I listened to my own advice. They’re well thought out – ThinkPads just get a little more love when it comes to design and build. While they’re not without fault, they are generally better than your average laptop.

The Dell laptops I’ve owned have felt cheap and both have gone in for repairs. The good news is, Dell support is pretty good about fixing things. But I wish I didn’t have to send them in for repairs. Sidenote: my old ThinkPads have made for excellent loaners during repair periods. Dell really should be cheap and cheerful, but the whole experience leaves me feeling a bit “meh.”

Continue reading →

The latest issue on my 2019 XPS 13 is that the keyboard appeared to be getting out of whack. I noticed the control and function keys were sitting at different angles.

Then I realized: my battery is puffed. I confirmed it when the lid wouldn’t close fully.

After reflecting on the situation, I realized my laptop has spent the better part of 1.5 years (since COVID started) operating on AC power. Normally on my ThinkPad I’d use TLP to keep my normal battery charge at around 60-80%. But those features aren’t available on my XPS:

$ sudo tlp-stat
...
+++ Battery Features: Charge Thresholds and Recalibrate
natacpi    = inactive (laptop not supported)
tpacpi-bat = inactive (laptop not supported)
tp-smapi   = inactive (laptop not supported)
...

Other TLP features (like disabling wifi when plugged into the wired network) do work on my XPS, so I leave it installed & enabled. For battery management, you must use Dell’s own Command Configure tool: cctk

There’s a great write-up on the XPS 7390 over in the Arch Linux wiki.

So I set up cctk to keep my (new, now replaced) battery at 80%.
sudo crontab -l

...
@reboot /opt/dell/dcc/cctk --PrimaryBattChargeCfg=Custom:75-80

And I have a shell script that I can run to bring the charge up to 100%:
vi ~/bin/full_charge.sh

#!/bin/sh
sudo /opt/dell/dcc/cctk --PrimaryBattChargeCfg=Standard

Do yourself a favor – next time get a ThinkPad.

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A coworker gave a lunch and learn about mechanical keyboards. I should have known it would be an entrance to a black hole… it all started 25 years ago with my beloved Zeos Keyboard with Alps keygates – which I consequently wrecked after spilling a beer into it 🍺 Then onto my HHKB Lite2 which I still have but need a host of adapters to connect its PS/2 connector.

Now I’m entering the modern mechanical era with a Keychron K6 – a 65% keyboard that closely resembles my HHKB layout. It has Gateron Blue (light and clicky) switches that remind me of my famed Zeos board. Here’s the original layout:

My first issue is I have a bit of OCD when it comes to pairing. I expect insert/del, home/end, and page up/down to be at least near each other, if not next to each other. So I changed the keycaps in the far right row, around the corner to the FN1/2 keys. I used low(ish) profile DSA keys on this edge to mimic the lower arrow keys from the HHKB. Also I got custom colored beige/blue FN1/FN2 keys to quickly remind me that FN1 is for the gold functions and FN2 is for blue.

Now I needed to change what the swapped keys did when I pressed them…

Continue reading →

When it comes to customizing keyboards in Linux, there are at least 10 ways to skin this cat 😼 but for a one-to-one replacement, evdev is the answer. Why? Because it’s low-level enough to work with everything, whether you use Xorg or Wayland. It even works in the console.

Getting information about your keyboard

For our research you’ll probably need to install a couple of things:

sudo apt install evtest evemu-tools

You can use evemu-describe to get information about your keyboard. If you run evemu-describe without any arguments, you’ll be prompted to select the input device. I’ve highlighted my input in bold.

$ sudo evemu-describe
Available devices:
/dev/input/event0:	Lid Switch
...
/dev/input/event19:	Generic USB Audio
/dev/input/event20:	Keychron K6 Keyboard
/dev/input/event21:	Keychron K6 Consumer Control
/dev/input/event22:	Keychron K6 System Control
/dev/input/event23:	BluetoothMouse3600 Mouse
/dev/input/event24:	BluetoothMouse3600 Consumer Control
Select the device event number [0-24]: 20
# EVEMU 1.3
# Kernel: 5.11.0-27-generic
# DMI: dmi:bvnDellInc.:bvr1.7.0:bd10/22/2020:br1.7:svnDellInc.:pnXPS137390:pvr:rvnDellInc.:rn0G2D0W:rvrA00:cvnDellInc.:ct10:cvr:
# Input device name: "Keychron K6 Keyboard"
# Input device ID: bus 0x05 vendor 0x5ac product 0x24f version 0x11b
# Supported events:
#   Event type 0 (EV_SYN)
#     Event code 0 (SYN_REPORT)
...
#     Event code 15 (SYN_MAX)
#   Event type 1 (EV_KEY)
#     Event code 1 (KEY_ESC)
...
# Properties:
N: Keychron K6 Keyboard
I: 0005 05ac 024f 011b
...

Take note of the properties line towards the bottom:
I: 0005 05ac 024f 011b
It is the Bus/Product/Vendor/Version identifier that we’ll use that to identify the keyboard in our hardware DB file.

Gather Keycode & Scancode Information

Along with the Bus/Product/Vendor/Version identifier, you’ll need scancodes and keycodes for our configuration file.

The keys I wanted to replace on the far right are:

Home -> Grave/Tilde
Page Up -> Insert
Page Down -> Delete

To get scancodes, run sudo evtest and select the input device you want to test (same as above), and then press the keys you want to switch out.

$ sudo evtest
No device specified, trying to scan all of /dev/input/event*
Available devices:
/dev/input/event0:	Lid Switch
...
/dev/input/event19:	Generic USB Audio
/dev/input/event20:	Keychron K6 Keyboard
/dev/input/event21:	Keychron K6 Consumer Control
/dev/input/event22:	Keychron K6 System Control
/dev/input/event23:	BluetoothMouse3600 Mouse
/dev/input/event24:	BluetoothMouse3600 Consumer Control
Select the device event number [0-24]: 20
Input driver version is 1.0.1
Input device ID: bus 0x5 vendor 0x5ac product 0x24f version 0x11b
Input device name: "Keychron K6 Keyboard"
Supported events:
  Event type 0 (EV_SYN)
  Event type 1 (EV_KEY)
    Event code 1 (KEY_ESC)
...
Testing ... (interrupt to exit)
Event: time 1629497486.881450, type 4 (EV_MSC), code 4 (MSC_SCAN), value 70028
Event: time 1629497486.881450, type 1 (EV_KEY), code 28 (KEY_ENTER), value 0
Event: time 1629497486.881450, -------------- SYN_REPORT ------------
Event: time 1629497489.406440, type 4 (EV_MSC), code 4 (MSC_SCAN), value 7004a
Event: time 1629497489.406440, type 1 (EV_KEY), code 102 (KEY_HOME), value 1
Event: time 1629497489.406440, -------------- SYN_REPORT ------------

For example, the scancode for the HOME key is 7004a. The keycodes are printed in all caps, such as KEY_HOME. You can also look up keycodes here, or if you’re trying to add a new key that isn’t on your keyboard, you can find all keycodes in /usr/include/linux/input-event-codes.h

We’re going to put this all into a hardware DB file. The filename is arbitrary, as long as it has a .hwdb extension. I put a number at the beginning because config files like this are loaded in filename order. If something should load before or after, it can use a lower/higher number (respectively).

sudo vi /etc/udev/hwdb.d/50-k6keyboard-bt.hwdb

# Input device ID: bus 0x5 vendor 0x5ac product 0x24f version 0x11b
# evdev:input:b<bus_id>v<vendor_id>p<product_id>e<version_id>-<modalias>
evdev:input:b0005v05ACp024F*
 KEYBOARD_KEY_7004a=grave
 KEYBOARD_KEY_7004b=delete
 KEYBOARD_KEY_7004e=insert

It took several attempts to get this right. I didn’t realize that the format is very particular and it should look something like: b0000v0000p0000e0000*. Don’t include the hex prefix of 0x. Also hex values must be capitalized in udev version 220 and above. Lastly, put a * at the end to capture all the versions. You can verify your version of udev by running:

$ udevadm --version
245

The keycode remapping lines must look like this:
KEYBOARD_KEY_<scancode>=<keycode>
The keycodes must be lowercase on the right side of the .hwdb file.

Build & Test

Once your hardware DB file is saved, you can test out the setup, by running these commands:

$ sudo systemd-hwdb update
$ sudo udevadm trigger
$ udevadm info /dev/input/event20
P: /devices/pci0000:00/0000:00:14.0/usb1/1-7/1-7:1.0/bluetooth/hci0/hci0:256/0005:05AC:024F.0007/input/input41/event20
N: input/event20
L: 0
E: DEVPATH=/devices/pci0000:00/0000:00:14.0/usb1/1-7/1-7:1.0/bluetooth/hci0/hci0:256/0005:05AC:024F.0007/input/input41/event20
E: DEVNAME=/dev/input/event20
E: MAJOR=13
E: MINOR=84
E: SUBSYSTEM=input
E: USEC_INITIALIZED=4366743414
E: KEYBOARD_KEY_7004a=grave
E: KEYBOARD_KEY_7004b=delete
E: KEYBOARD_KEY_7004e=insert
E: ID_INPUT=1
E: ID_INPUT_KEY=1
E: ID_INPUT_KEYBOARD=1
E: ID_BUS=bluetooth
E: XKBMODEL=pc105
E: XKBLAYOUT=us
E: BACKSPACE=guess
E: LIBINPUT_DEVICE_GROUP=5/5ac/24f:90:78:41:ca:1e:02
E: TAGS=:power-switch:

The first command (systemd-hwdb update) reads the hwdb files and rebuilds the binary hardware database from the text files. The second (udevadm trigger) tells udev to (re)scan hardware for matches. The last (udevadm info) helps verify that the configuration – remember to replace event20 with your device ID.

You can see in the output that my KEYBOARD_KEY entries are there and they do indeed work 💪 It will also be there after you reboot.

My next step will be adding home/end and page up/down modifiers to my arrow keys…

← Summary Only

Justin Foell

Technology, Bicycling, Hobbies, Kids, Life.

Category Archives: Ubuntu

Ubuntu 22.04 & aptX Bluetooth codec

AptX on Ubuntu 22.04

Enable PipeWire on Ubuntu 22.04

Install

Configure

ALSA

PulseAudio

Bluetooth

Done

Coming soon..

Unblock Port 5060 on Comcast / xfinity

Approach 1 (trying to fix the problem directly)

Approach 2 (playing the game)

What’s really going on?

Remove /etc/pipewire

PipeWire Debugging

Dell XPS Developer Edition Battery Puffed

Remapping Keyboard Keys in Ubuntu with udev / evdev

Getting information about your keyboard

Gather Keycode & Scancode Information

Build & Test