Review on 🔊 Optimal Shop USB 2.0 External Sound Card 6 Channel 5.1 Surround Adapter Audio S/PDIF for PC -Blue: Enhance Your PC Audio Experience by Ben Diesel

I needed a cheap USB multi-channel audio device for a project, so I gave it a try. This worked somewhat immediately on both Windows and Linux. It is based on CMedia CM6206-LX. In short, it's a bad hardware/PCB design with wrong components, open bugs and it doesn't work much. Read the technical details below. I found a few issues with the PCB design that I needed to fix to make it work better: - The IC's analog power input is connected to a 3.3V LDO, which compares to the 4.5-5.5 -V-ARDD specification violation. I cut the track and soldered it to 5V through a choke and bridged it with a cap. Although the microcircuit technically worked with a voltage of 3.3 V, it had a reduced input and output signal amplitude. - The output electrolytic caps are installed upside down, resulting in DC leakage at the outputs. I had to turn her over. - The line input is AC coupled via 0.1uF capacitors, which is too low for the IC's input impedance (20kΩ according to the datasheet) and causes a large drop at low frequencies. I replaced them with 10uF electrolytic capacitors and got a fairly flat frequency response. There's another problem I couldn't fix: the data written from the line-in has a significant DC offset. The problem seems to be in the chip itself.