The earphones are a simple case: a probable break in the wire where it enters the plug results in silence in the right ear. I'm a bit peeved, as I would have thought I'd get more than 6 months of use out of them, given that they are proper earphones (Sennheiser MX 350), and so Should Not Break. And, of course, I can't find the recipt for them. I have a sneaking suspicion that the recipt is in a box in my room at home, but I'm not there so I can't check myself. Ah well, at least I have the backup earphones (Creative branded, but they actually have bass).
Later on, I then decided to tinker with the innards of my desktop. This tinkering, in the end, resulted in me removing the graphics card to gain access to the disk cage, removing said disk cage, adding a hard disk, adding a PCI IDE controller card, moving the optical drives down a slot (arrangement from top to bottom is 3x5.25" half-height external with slide mounting, 1x3.5" external drilled for FDD, 1x3.5" external drilled for FDD or HDD, 2x3.5" internal drilled for HDD), rerouting all the power, rerouting all the IDE cables, rerouting the floppy cable, adding an IDE cable for the new disk, attacking the dust bunnies with a can o' air, removing an unneeded audio cable, cursing the case design several times, contemplating getting my own case built from scratch, and finally replacing the disk cage and graphics card. In roughly that order.
Whereupon the computer refused to power on. After much cursing and easter-egging of various parts (new hardware, graphics card), I unplugged the Antec PSU and bodged a feed from the precursor, at which point everything started working. After a bit of headscratching Nick suggested trying the Antec again, and lo and behold it too worked.
Obviously the computer was feeling neglected and wanted some attention.