This is in OSX, right? I know Scott Brown had problems with SparkME on his Powerbook. I don't think he ever solved them, though a different version of Spark may work - I haven't heard from him on that issue yet. I recommend DP4, but make sure you get 4 and not 4.01 if you decide on this because there is a bug in 4.01.
I use DP3 in OS9 on a Pismo and once I configured the system, I have NEVER (knock wood) had a problem recording.
-Matt