I haven't tried this on a Zen but I have repaired headphone sockets on small, cheap no-name Chinese players. This involved disassembling the case and re-soldering a cracked joint between the socket and the circuit board. In fact, I re-soldered all the joints on the socket because I could not identify which was broken.
Possibly it was easier with a cheap player because it was pretty crudely built -- and of course the cost of messing up was less of an issue.
I suspect it comes down to your experience of soldering.
To help yourself, take photos as you disassemble any complex components and make sure your soldering iron is low-wattage with a fine tip. If possible, test the player before re-assembly.
I've had my Creative Zen Micro (4GB) going on four years now. That's a pretty good length of time to hold on to any MP3 player, to be sure, but it still works and I have no desire to plunk down $150+ on a new device if this one is still working.
The key here is that I believe I am experiencing problems with the headphone jack (not the headphones as I've tried 3 different sets and all have the same problem). I can no longer keep the player in my jacket pocket or even nudge the earphones in the slightest without the sound getting all crappy on me. I've discovered that this model, very early on, had a headphone jack issue and I'm thinking it's only creeping up on lucky 'ol me just now. I see online tutorials on how to fix the problem on your own by taking the unit apart and using everything from tiny screwdrivers to scissors to a soldering iron! Anyone have any experience doing this? Should I be concerned?
-Jason

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