The iRiver H340 is a portable music player with a 40Gb, 2.5-inch hard disk drive. It has a headphone output, a line level output and both line input and a built-in microphone. There's a built-in FM radio, which can also be used as a recording signal source.
I acquired the H340 from FreeCycle, without any of the accessories. I suspected that the lithium-ion battery had become discharged, so I found a 5V power supply and charged it up. The H340 worked just fine, and I was able to use it to test some other audio gear that I had also got from FreeCycle.
My mistake was to use the H340 to test a 70+70Watt in-car amplifier that incorporates a step-up power supply. Somehow, I connected the H340 to the amp while a large DC offset was present at the input terminal. This destroyed the headphone output on one channel. Foolishly, I tried again with the line level output before realising (with horror) what had happened. So I now had an MP3 player with both line and headphone outputs dead on the right channel.
The unit can be opened up by unscrewing several tiny screws from the case. The H340 opens up to reveal the battery, hard disk drive, PCB and some blue rubber shock-absorbing material.
There's a single chip for all of the digital-to-analog and analog-to-digital functions, as well as acting as the headphone amplifier and line output driver. Clearly, this is the chip that I'd blown up.
I obtained a replacement DAC/ADC chip, UDA1380TT, from RS Components, order code 484-1007. It's a 32-pin surface-mount chip, 0.65mm lead pitch. It sounds tiny, but it's not too difficult to solder with a fine tip, good lighting and a stereo microscope. I removed the defective chip by carefully cutting its leads off with a sharp knife, before cleaning up the solder pads on the PCB.
Photos of the chip removal and replacement are in this Flickr set.
Reassembly is the reverse of disassembly.