Protyposis

Travelling through time & space in real-time...

ClockDrift: On-the-fly measurements of clock drift in multimedia devices

Over the last year, I’ve been extensively researching and wasting time on an effect called clock drift in the multimedia domain. Clock drift is the deviation of a clock’s speed from the word time standard‘s speed, resulting in shifts in sampling rates, and this shift leads to parallel recordings from different devices not being synchronizable without manual post-processing. Because each recording is sampled a bit differently, they all run at a slightly different speed when played back in parallel on a single device, like it happens in a non-linear editing system on a computer workstation. To conclude this topic, I have just published an Android app called ClockDrift, which helps to measure drift in multimedia devices. I have also written an accompanying ClockDrift App User Guide and a general introduction into the topic, Clock Drift in Multimedia Recordings.

ClockDrift
Developer: Protyposis
Price: Free

Seat Leon 1P 2010 Facelift AUX Mid-Tones Fix

Some early Seat Leon 1P Facelift cars with Media-In functionality (AUX, USB & iPod support) suffer from a problem where the mid-tones on the left channel are missing when listening to analog audio through the AUX input, which includes listening from an iPod with the iPod adapter cable. This can be resolved in a couple of minutes by replacing the old AUX port with a new and fixed revision.

The problem is a faulty circuit board in the combined USB/AUX port (CUP) panel, where the lines of the 3.5mm stereo plug are incorrectly wired. The left channel is flipped with the right channel, and even worse, the right channel is flipped with ground.

Rayovac Car USB Charger AC Fast Charging Mod

The Rayovac PS70 Dual USB Car Charger is a nice little gadget that I’m using in my car to charge my smartphone. It can be had for just a few bucks, e.g. $8 at WalMart. Although its output current is specified at 2A (or 2.1A in newer versions), it charges many devices at a low current of only 0.5A because it doesn’t correctly identify itself as a fast charger. This can be easily fixed.

A lot of devices (e.g. Samsung Galaxy S II, LG Nexus 4, LG Nexus 5) do not switch into fast charging mode (called AC mode in Android), because they do not detect the Rayovac as a charger; instead, they stay in data transfer mode (USB mode) and charge at 0.5A. That’s not only very slow, but also not enough for charging or even just compensating battery drain when using the phone for music and navigation while driving.

Fortunately, there’s an easy fix if you haven’t got two left hands. All you need is a soldering iron, solder and a flat screwdriver or something similar.