Hi,
If there is no click/or pop in the waveform it is processing.
Have you tried to listen to the file using QuickTime ( Logic closed ) can you still hear the click/pop? If not it is a bandwidth issue between Logic and the Interface. As others have mentioned you most likely need to optimize Logic to the interface. If you are using an External drive to record to this can also cause problems if it is slow.
A Few Tips:
1) Never use a USB hub with external drives or the interface that are being used by Logic
2) Make sure that your Interface has current and updated drivers.
3) Research best settings for your interface in regards to Preferences: General: Devices ( Buffer, Processing Threads, Buffer Range etc. )
4) If the files are on an external drive. Save a package to an internal drive and test. This eliminates the performance of the external drive.
Hope this helps