If you are using the MOTU PCI-324 card with the TC PowerCore, there are some situations where you may experience popping and clicking. If this is the case, please try the following:
What to do in this situation:
1. Disable all unused channels of the sound card to "off" in the PCI-324 Console.
2. If there is a PCI Graphics accelerator card in use, consider getting a more advanced AGP model, which uses a different bus as well as a different slot. (Provided you have a G4 computer.)
3. Raise the hardware buffer size