Ok, I have more information about this problem.

I can fix the problem temporarily by following Paul's instructions on running the player binary from the command prompt here. This will fix my player, but only until I modify the database.

Whenever I try to change the database, either with Jemplode or Emplode, the player will somehow lose the database, and display the messages I referenced above in the boot log:

! playerdb.cpp : 182:Failed to build dynamic database (status=0xc004401a).