In this video, I show how I diagnosed and repaired an ECHO AUDIOFIRE 4 external FireWire sound-card. The card had developed a fault on channel 1, one of the two front input channels. It presented as a pumping and or ticking effect after a few moments. The fault was a blown pre-amp chip which I suspect had been overloaded with input.

Diagnosis was by using IsoPropyl alcohol placed on the two pre-amp chips and as they began to operate, the faulty one got hot and the alcohol evaporated. It was also hot to touch after a few minutes.

Being surface-mounted, it took using a hot-air tool at 350°C to remove it from the board after sourcing a replacement from RS Components

A successful repair which I have now carried out several times.