Workaround/solution for Audio crash/hang loud beep after a certain period – rt5650 on HP Chromebook G5

By , 2023-01-09 19:16

Installing Ubuntu 22.04 or Linux Mint on an HP Chromebook G5 EE works fine, except for the audio hanging and producing a loud beep until pulseaudio is restarted. The solution :

On 12/18/22 7:02 AM, Mark Hills wrote:
HP Chromebook (11a, G5 “Setzer”) uses snd_soc_sst_cht_bsw_rt5645 module
and presents a device “rt5650”.

can you share the result of ‘aplay -l’, wondering which platform driver you are using.
Audio works briefly, until after about 30 seconds it’s interrupted by a
square wave or short buffer cycling.

If this is with the SOF driver, there’s a known issue and a known workaround, please add this to /etc/modprobe.d/alsa-base.conf

options snd_sof sof_debug=1
— Read on

PowerShell one-liner: Convert FLAC to MP3 using ffmpeg

By , 2022-08-09 21:07

obviously requires ffmpeg in PATH, I use the Windows binaries from here:

Get-ChildItem -Filter '*.flac' ".\inflacfilesdir\" | ForEach-Object { ffmpeg -i $_.FullName -c:a libmp3lame -q:a 0 -map_metadata 0 ".\outmp3filesdir\$($_.Basename).mp3" }
  • -c:a libmp3lame = use lame encoder
  • -q:a 0 = equivalent to lame V0 VBR
  • -map_metadata 0 = copy metadata tags, including embedded album art
  • inflacfilesdir and outmp3filesdir should be modified to point to corresponding directories. They can also be set to the same value if you want the .mp3 files to be created in the same place as the .flac files.

A little collection of Windows ME (9x) Blue Screens of Death

By , 2021-08-03 22:58

Windows ME BSODs (Exception, System Busy, and WARNING) Captured directly from VMware Workstation today.

I had found in the past that it was a bit hard to find clean, unedited, pixel-perfect copies of the Blue Screens of Death, so when my Windows ME VM crashed today I knew it was time to save these for the future. These are pretty much the same as the ones that would appear in Windows 95 and Windows 98.

First the classic “An exception 0D has occurred” BSOD

Next, System is busy

and last but not least, WARNING system has become unstable

WiFi network data analysis – Downtown Toronto

By , 2021-03-20 23:00

Installed a new Ubiquiti USG at an office downtown today, and noticed that in the 8 hours since the system was first up, it had detected over 800 nearby networks. I decided to analyze the data a bit for fun.

First, the channel. I was surprised to see that over half of all detected APs were on channel 6.

It does make sense that there are far more 2.4GHz APs detected, since it has better signal penetration.

Next up, security standards.

Nearly 90% of APs are using WPA2 of some sort, and just over 10% are open. Less than 1% use WPA.

Now, arguably the most interesting – the AP manufacturer, according to OUI lookup.

Note: some OUIs were not recognized, so the dataset is slightly less than 800 here.

In the manufacturer breakdown we se a lot of the usual brands – Cisco, Aruba and Ubiquiti are in the top. Technicolor, Sagemcom, ASUS, HP, Juniper, Sonicwall are all also common network vendors. But what of the others?

The biggest “unusual” vendor we see is Mitsumi. Mitsumi is generally known as an OEM that manufactures PC peripherals and input devices – mice, keyboards, floppy and optical drives, and quite a few game consoles. It’s not surprising that they would make WiFi radios, but I wouldn’t expect their OUI to be used as an OEM.

Looking a bit further at the data, most of the Mitsumi networks’ SSIDs are in the format “WiFi Hotspot 0000” (where 0000 is a random 4 digits). However, a few of them had names such as “Cruze”, “Volt”, “Equinox” and “Malibu”. So, apparently Mitsumi manufactures the WiFi radio for the GM OnStar car hotspots.

Continuing on with the less-known OUI vendors, we also see Visteon, Continen (Continental), Harman/B (Harman/Becker), and AlpsElec (Alps Electric).

Alps, like Mitsumi, is an OEM known for PC peripherals – particularly keyboards and laptop touchpads. In this case, the SSIDs for the Alps APs are all some variant of “MB Hotspot 000” – so they are Mercedes-Benz car hotspots.

So, unsurprisingly, the other 3 are also car electronics OEMs.

Visteon – spun off from Ford in 2000, they specialize in car infotainment and other electronics systems.
Continental Automotive Systems – The electronics systems branch of German company Continental Tire.
Harman/Becker – a division of Samsung, specialized in car electronics, resulting from the Harman company’s acquisition of Becker, a German car radio manufacturer.

Today’s takeaway: a LOT of cars have WiFi hotspots built-in these days!

Ontario form 4383-80 English form-fillable PDF

By , 2021-03-07 22:05

Got frustrated that this form wasn’t available as a proper PDF form, so made it myself. Intended only as a convenience for those who wish to use it. PDF is not password-protected or signed.

Download a copy of the 4383-80E pdf form (Patient Enrolment and Consent to Release Personal Health Information) below.

Xircom RealPort 56k modem + 10/100 Ethernet drivers

By , 2021-01-27 13:35

Intel used to host these on their website, but took them down in a purge a few years back. So here are the drivers I saved a while back.

XBEM – Ethernet + Modem
XBE – Ethernet only

The 314 ones are from Intel (2000), the others are from Dell and a bit older (1999). All versions in one 7-zip file.

NVIDIA GPU ‘passthrough’ to lxc containers on Proxmox 6 for NVENC in Plex

By , 2020-12-06 19:19

I’ve found multiple guides on how to enable NVIDIA GPU access from lxc containers, however I had to combine the information from multiple sources to get a fully working setup. Here are the steps that worked for me.

  1. Install dkms on your Proxmox host to ensure the nvidia driver can be auto-updated with new kernel versions.
    # apt install dkms
  2. Download the latest nvidia binary driver supported by nvidia-patch.
    Head over to and get the latest supported driver version listed there.
  3. Download the nvidia-patch repo
    git clone
  4. Install the driver from step 1 on the host.
    For example, ./
  5. Run the nvidia-patch/ script on the host.
  6. Install the same driver in each container that needs access to the Nvidia GPU, but without the kernel module.
    ./ --no-kernel-module
  7. Run the nvidia-patch/ script on the lxc container.
  8. On the host, create a script to initialize the nvidia-uvm devices. Normally these are created on the fly when a program such as ffmpeg calls upon the GPU, but since we need to pass the device nodes through to the containers, they must exist before the containers are started.

    I saved the following script as /usr/local/bin/nvidia-uvm-init. Make sure to chmod +x !
## Script to initialize nvidia device nodes.

/sbin/modprobe nvidia

if [ "$?" -eq 0 ]; then
  # Count the number of NVIDIA controllers found.
  NVDEVS=`lspci | grep -i NVIDIA`
  N3D=`echo "$NVDEVS" | grep "3D controller" | wc -l`
  NVGA=`echo "$NVDEVS" | grep "VGA compatible controller" | wc -l`

  N=`expr $N3D + $NVGA - 1`
  for i in `seq 0 $N`; do
    mknod -m 666 /dev/nvidia$i c 195 $i

  mknod -m 666 /dev/nvidiactl c 195 255

  exit 1

/sbin/modprobe nvidia-uvm

if [ "$?" -eq 0 ]; then
  # Find out the major device number used by the nvidia-uvm driver
  D=`grep nvidia-uvm /proc/devices | awk '{print $1}'`

  mknod -m 666 /dev/nvidia-uvm c $D 0
  mknod -m 666 /dev/nvidia-uvm-tools c $D 0
  exit 1

Next, we create the systemd service files to start this script, and the nvidia-persistenced.

# nvidia-uvm-init.service
# loads nvidia-uvm module and creates /dev/nvidia-uvm device nodes

Description=Runs /usr/local/bin/nvidia-uvm-init


# NVIDIA Persistence Daemon Init Script
# Copyright (c) 2013 NVIDIA Corporation
# Permission is hereby granted, free of charge, to any person obtaining a
# copy of this software and associated documentation files (the "Software"),
# to deal in the Software without restriction, including without limitation
# the rights to use, copy, modify, merge, publish, distribute, sublicense,
# and/or sell copies of the Software, and to permit persons to whom the
# Software is furnished to do so, subject to the following conditions:
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
# This is a sample systemd service file, designed to show how the NVIDIA
# Persistence Daemon can be started.

Description=NVIDIA Persistence Daemon

ExecStart=/usr/bin/nvidia-persistenced --user nvidia-persistenced
ExecStopPost=/bin/rm -rf /var/run/nvidia-persistenced


Next, symlink the two service definition files into /etc/systemd/system
cd /etc/systemd/system
# ln -s /usr/local/lib/systemd/system/nvidia-uvm-init.service
# ln -s /usr/local/lib/systemd/system/nvidia-persistenced.service

and load the services
# systemctl daemon-reload
# systemctl start nvidia-uvm-init.service
# systemctl start nvidia-persistenced.service

Now you should see all the nvidia device nodes have been created
# ls -l /dev/nvidia*
crw-rw-rw- 1 root root 195, 0 Dec 6 18:07 /dev/nvidia0
crw-rw-rw- 1 root root 195, 1 Dec 6 18:10 /dev/nvidia1
crw-rw-rw- 1 root root 195, 255 Dec 6 18:07 /dev/nvidiactl
crw-rw-rw- 1 root root 195, 254 Dec 6 18:12 /dev/nvidia-modeset
crw-rw-rw- 1 root root 511, 0 Dec 6 19:00 /dev/nvidia-uvm
crw-rw-rw- 1 root root 511, 0 Dec 6 19:00 /dev/nvidia-uvm-tools

total 0
cr-------- 1 root root 236, 1 Dec 6 18:07 nvidia-cap1
cr--r--r-- 1 root root 236, 2 Dec 6 18:07 nvidia-cap2

Check the dri devices as well
# ls -l /dev/dri*
total 0
drwxr-xr-x 2 root root 100 Dec 6 17:00 by-path
crw-rw---- 1 root video 226, 0 Dec 6 17:00 card0
crw-rw---- 1 root video 226, 1 Dec 6 17:00 card1
crw-rw---- 1 root render 226, 128 Dec 6 17:00 renderD128

Take note of the first number of each device after the group name. In the listings above I have 195, 511, 236 and 226.

Now we need to edit the lxc container configuration file to pass through the devices. Shut down your container, then edit the config file – example /etc/pve/lxc/117.conf. The relevant lines are below the swap: 8192 line

arch: amd64
cores: 12
features: mount=cifs
hostname: plex
memory: 8192
net0: name=eth0,bridge=vmbr0,firewall=1,gw=,hwaddr=4A:50:52:00:00:00,ip=,type=veth
onboot: 1
ostype: debian
rootfs: local-lvm:vm-117-disk-0,size=250G,acl=1
startup: order=99
swap: 8192

lxc.cgroup.devices.allow: c 195:* rwm
lxc.cgroup.devices.allow: c 226:* rwm
lxc.cgroup.devices.allow: c 236:* rwm
lxc.cgroup.devices.allow: c 511:* rwm
lxc.mount.entry: /dev/dri dev/dri none bind,optional,create=dir
lxc.mount.entry: /dev/nvidia-caps dev/nvidia-caps none bind,optional,create=dir
lxc.mount.entry: /dev/nvidia0 dev/nvidia0 none bind,optional,create=file
lxc.mount.entry: /dev/nvidiactl dev/nvidiactl none bind,optional,create=file
lxc.mount.entry: /dev/nvidia-uvm dev/nvidia-uvm none bind,optional,create=file
lxc.mount.entry: /dev/nvidia-modeset dev/nvidia-modeset none bind,optional,create=file
lxc.mount.entry: /dev/nvidia-uvm-tools dev/nvidia-uvm-tools none bind,optional,create=file

Now, start your container back up. You should be able to use NVENC features. You can test by using ffmpeg:
$ ffmpeg -i dQw4w9WgXcQ.mp4 -c:v h264_nvenc -c:a copy /tmp/rickroll.mp4

You should now have working GPU transcode in your lxc container!

If you get the following error, recheck and make sure you have set the correct numeric values for lxc.cgroup.devices.allow and restart your container.

[h264_nvenc @ 0x559f2a536b40] Cannot init CUDA
Error initializing output stream 0:0 -- Error while opening encoder for output stream #0:0 - maybe incorrect parameters such as bit_rate, rate, width
or height
Conversion failed!

Another way to tell the values are incorrect is having blank (———) permission lines for the nvidia device nodes. You will get this inside any containers that are started before the nvidia devices are initialized by the nvidia-uvm-init script on the host.

$ ls -l /dev/nvidia*
---------- 1 root root        0 Dec  6 18:04 /dev/nvidia0
crw-rw-rw- 1 root root 195, 255 Dec  6 19:02 /dev/nvidiactl
---------- 1 root root        0 Dec  6 18:04 /dev/nvidia-modeset
crw-rw-rw- 1 root root 511,   0 Dec  6 19:02 /dev/nvidia-uvm
crw-rw-rw- 1 root root 511,   1 Dec  6 19:02 /dev/nvidia-uvm-tools

Sometimes, after the host has been up for a long time, the /dev/nvidia-uvm or other device nodes may disappear. In this case, simply run the nvidia-uvm-init script, perhaps schedule it to run as a cron job.

Install OpenSSH Server on Windows 10

By , 2020-07-14 23:52

In an Administrator PowerShell session:

# Install the OpenSSH Server
Add-WindowsCapability -Online -Name OpenSSH.Server~~~~
# Set service to Automatic startup
Set-Service -Name sshd -StartupType 'Automatic'
# Start service
Start-Service sshd
# Confirm the Firewall rule is configured. It should be created automatically by setup. 
Get-NetFirewallRule -Name *ssh*

Force amdgpu instead of radeon driver on Ubuntu 19.04 (Pop!_OS 19.04)

By , 2019-04-29 09:55

Update: Even after doing all this the system still locks up randomly when using the amdgpu driver.

I’m running dual AMD FirePro W2100 driving 3 monitors in my workstation. Since installing the cards I’ve been suffering random freezes/graphical lockups that seemed to be related to 3D. They occurred typically during an animation in gnome-shell, or when using Firefox or Chrome with hardware acceleration. Most times, I was able to recover by logging in to the machine via ssh and sending killall -HUP to the appropriate process (usually gnome-shell). Every time this happened, syslog would be full of GPU faults:

[ 2482.763707] radeon 0000:02:00.0: GPU fault detected: 146 0x0468100c
[ 2482.763708] radeon 0000:02:00.0:   VM_CONTEXT1_PROTECTION_FAULT_ADDR   0x0011173E
[ 2482.763709] radeon 0000:02:00.0:   VM_CONTEXT1_PROTECTION_FAULT_STATUS 0x0805000C
[ 2482.763710] VM fault (0x0c, vmid 4) at page 1120062, read from CB (80)
[ 2482.763713] radeon 0000:02:00.0: GPU fault detected: 146 0x0408500c
[ 2482.763714] radeon 0000:02:00.0:   VM_CONTEXT1_PROTECTION_FAULT_ADDR   0x00111744
[ 2482.763715] radeon 0000:02:00.0:   VM_CONTEXT1_PROTECTION_FAULT_STATUS 0x0805000C
[ 2482.763717] VM fault (0x0c, vmid 4) at page 1120068, read from CB (80)

I tried updating my kernel (going from Ubuntu 18.04 to 18.10 and even reinstalling with Pop!_OS 18.10 than 19.04) and updating graphics drivers using the oibaf ppa, to no avail. Finally found what seems to be the solution on HackerNews (thanks danieldk) – force the use of the newer amdgpu driver rather than the older radeon driver. The W2100 is a first-generation GCN chip and so is supported by both drivers, and radeon is chosen as the default. To force amdgpu, you need to pass the kernel flags

amdgpu.si_support=1 radeon.si_support=0 amdgpu.cik_support=1 radeon.ciksupport=0

In Ubuntu, add these to GRUB_CMDLINE_LINUX_DEFAULT in /etc/default/grub, then run update_grub. Pop!_OS doesn’t use grub, so you need to add each flag using kernelstub -a amdgpu.si_support=1 and repeating for each of the 4.

So far, my system seems stable since this change. I will update this post if anything changes.

pulseaudio-dlna + Yamaha AV Receiver RX-V573

By , 2018-09-03 15:52

It “just works!”

Install pulseaudio-dlna from Ubuntu default repos, then run pulseaudio-dlna. The first time, it failed, but I think that’s because the receiver was switched off. Console output did show it had been detected though. After switching on the receiver then running pulseaudio-dlna again, it redirected my currently playing audio to the receiver after a few seconds! So far this is the first time I’ve managed to get DLNA live streaming working with this receiver in 5 years of owning it.

Custom theme by me. Based on Panorama by Themocracy