How Does Timecode Vinyl Actually Work? (Pt. 2)

This is a mirror of a blog post that was published on the website of Mixxx, an open-source DJ software. You can read the original post over at

In the last post, I explained how a basic relative-mode Digital Vinyl System (DVS) works. But there are two problems …

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How Does Timecode Vinyl Actually Work? (Pt. 1)

This is a mirror of a blog post that was published on the website of Mixxx, an open-source DJ software. You can read the original post over at

Since the dawn of DJing, spinning vinyl records has never really gone out of fashion. Even when CDs became popular …

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Reversing Serato's GEOB tags

The popular DJ application Serato DJ Pro stores a lot data in GEOB-type ID3 tags of MP3 files. This way, users can share beatgrids, hot cue points, saved loops and more by just copying over an MP3 file.

Unfortunately, the format is not publicly documented. Thus, I figured it could …

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Using BurpSuite with qutebrowser

Some time ago I switched to qutebrowser, a keyboard-driven browser based on QtWebEngine. Thus, I had to adapt my BurpSuite setup for WebApp pentesting.

When pentesting web applications, a MITM proxy to log HTTP(S) requests is a necessity. Although open-source alternatives exist, PortSwigger's BurpSuite is the de-facto standard in …

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EFA Departure Monitor on the command line

I just hacked together a small shell script that gets departures from my local public transportation service. It will list upcoming departures at a stop. You can find the script here.

Getting Started

You can either use the stop name:

$ ./ "Dortmund Hbf"

Or you can use the stop …

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Fixing WiFi Multicast Flooding in bridged networks

I'm using MPD and PulseAudio's RTP multicasting to get a seamless multi-room audio experience.

Unfortunately, if you're using a network bridge to connect your wired and wireless LAN, using multicast RTP might have unintended consequences: All WiFi clients are flooded with multicast traffic, which can bring down the entire wireless …

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Upgrading iLO 4 on a HPE ProLiant MicroServer from Linux

I recently got my hands on a ProLiant MicroServer Gen8 by Hewlett Packard Enterprise (HPE). As I always do when setting up a server I checked if the device needs a firmware upgrade.

And indeed it did: It's version of Integrated Lights-Out (iLO) 4, its built-in server provisioning and management …

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Generating syntax diagrams using the LaTeX rail package

If you ever had the need to add syntax specifications to your document, you basically have two options: Either write down the syntax in the Backus-Naur form (BNF) (or one of its derivatives) or opt for a more graphical approach by adding "railroad diagrams". In my opinon, the latter are …

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How to create an UEFI-bootable Windows 7 stick from Linux.

In case you rely on Windows-only software or want to play a game that isn't on Linux yet, you might want to keep Windows 7 on a second partition. Although I didn't use it for months, I still keep one around just in case.

Unfortunately, it's not really straightforward to …

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Smartcard authentification in Chromium

My university's website for exam enrollment needs smardcard authentification, but only contains instructions how to use it with Mozilla Firefox. If you prefer Chrome/Chromium over Firefox and don't want to keep a Firefox installation around, you can do so - here are the instructions.

OT: The Ruhr-University of Bochum (RUB …

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