So far (<20 mins testing) it's working flawlessly!
What happened:
-I replaced the power lines and used the same battery.
-It worked fine for about 2 mins, and then the original problems popped back up.
-Then I noticed that it most certainly turned off when I advanced a track or two or hit the forward button the the turn wheel in general.
-This got me thinking about memory. I figured that advancing a track means that it has to read from the memory chip. And a derailed track of though highlighted that it usually shuts down during fairly heavy memory reading tasks.
-After a review of the two little black chips (one is memory, the other a processor, but I can't tell them apart) I found an infinitesimally small piece of solder between two wires off of one (probably shorting it). An exacto knife got it out fairly well.
-The problems didn't stop....
-I was about to reformat it (fat32 or fat) when I remembered an online post that said to format Zens in fat16, which wasn't an option in the uber-limited microsoft format utility.
-Went online Googling (it's a word, trust me) and eventually ended up with a ton of Creative Zen downloads. While searching I got a post about firmware for Zens, didn't know that there were different firmwares so I checked mine. Turns out, it had that very first firmware made for that mp3 player...
-Decided to update the firmware. Didn't work, got an error.
-Eventually found this:
http://www.mycreativefansite.com/2007/08/solution-semaphore-timeout-issue-on-zen.html#comment-form
-That fixed it, and once the new firmware was on it, everything's worked just fine.
My system for testing it it to turn the volume up to max and listen to all of the songs loop about four times.
A side-effect: it also fixed the volume up button, which was a bit sluggish before...
Shew, that's about it!
Thanks for the tips, if you guys hadn't brought it up and given advice I wouldn't have gotten it fixed.
EDIT:
New theory:
I finished testing the music player, it worked fine.
But I replaced the front of the calculator ontop, it returned to the same buggy state...
I took it out and had to flex the pcb near the turn wheel and the power contacts before it started working at that flawless level.
Maybe it's the pressure of the calculator messing it up, and when I 'fixed' it all I did was work with it until whatever was messed up got bent back into shape.....
(It works again, but I'm afraid to put it back into the calculator)
Any ideas?