Why is DoubleTwist launching and playing when I remove the headphones? I can't figure this out.

It appears that if I'm using Google Listen, and I remove the headphones from the jack, Listen automatically pauses (which I expect). But then DoubleTwist launches, chooses an MP3 at random, and starts playing (which I don't want).

Further, it seems that if I pause Listen before I pull the jack, it doesn't happen.

I say "seems" because I'm having trouble getting consistent results.

The long-and-short of it is that DoubleTwist is launching and playing a track when I remove the headphone jack for no apparent reason.

Has anyone else encountered this? How can I stop it?

(Unrooted Motorola Droid, Android 2.2)
Sounds just like a simple bug in DoubleTwist's app, and you should probably send them an email reporting it.  Programmers have access to system "events" (for lack of a better word) and we use these events in conjunction with the state of our app to trigger certain behaviors.  Like, if I created an app similar to DoubleTwist, I'd handle the system event of you unplugging your headphones to check if an mp3 is playing, and then I'd immediately pause it so that my app doesn't embarrass you by blasting your music out loud every time you unplug your headphones.  They could be performing this type of check (when receiving an alert from the system that the state of the user's headphone jack has changed) and either reading the state of the headphone jack incorrectly or evaluating the "are we playing audio" state of their own application (or both).