not enough detail yet for a repeatable test, but twice today the drs just disappeared (jvm crash??) when i pressed control-d (stop/play) while using drs.
version 1.0-rc6, windows xp, quicktime 7.2, java 1.6, on a relatively old/under-powered laptop.
there was always at least one audio/video. probably had been more at some point and some shut. Have not managed to reproduce yet (i.e. have run multiple videos, stopped, started, opened, closed) on same machine with no problems subsequently.