My D2 is acting weirdly. Maybe battery is shot??

[sps7]

I have the original D2, purchased in March 2008. It's worked fine 'til very
recently. About 1 week ago, I noticed I had trouble trying to shut it off.
Pushing the on-off switch seemed to work but then the D2 would start up again. It was difficult to shut off but I finally succeeded. Now things have worsened. I can't even use it because it keeps restarting over and over. Does this mean the battery is shot (which means I have to mail it in to Cowon to put in a new battery)? Or is something else wrong with my D2??

Just before this problem started, I had a corrupt music flac file on the D2. Only the first third of the file would play and then the D2 would just suddenly turn black and shut off due to some failure. I transferred all the flac files from my 16 GB card, deleted the bad flac file, and then transferred back to the 16 GB card all the flac music files. This seemed to work but then, at some point, the recent weird shutdown and start problems began. I don't know if the older bad-flac-file was the cause of the newer shutdown-start problems.

What could be wrong? What's the solution?

[Firmware: 2.59]

My computer OS is MEPIS 11, a Linux distro.

Thanks

[sps7]

Originally Posted by sps7

I have the original D2, purchased in March 2008. It's worked fine 'til very recently. ...........

I don't know if failing to plug in a headphone while starting up and when
turning off the D2 could be responsible for this sort of problem. You see, not long ago I started to use an arm band-type case for some mp3 player. [I got it in a thrift store or perhaps found it when students were moving out.] I had to burn a hole into the flap that seals the carrier shut. The hole is for the headphone jack. So I first start up the D2 with no headphone plugged in, pick my starting music and set it playing, then close the flap and plug in the headphone. Just before shutting off the D2, I unplug the headphones, take out the D2, and now have the problem of trying to turn off the D2.

I never did the above procedure for nearly all the time I've owned the D2. This procedure I described above is rather new. Is not having a headphone plugged into the D2 before starting it and when turning it off a possible cause of the problem?