You can try these things;
1. Maybe set the snap to grid so each loop point starts and ends on a measure
2. Maybe you need to have devote more ram to Superior drums
3. Maybe you could freeze Superior drums
4. Maybe raise your ASIO buffers or WDM slider.
5. Maybe you can raise the playback buffers to 512 or 256 or 1024, depending on what you have it set to now.
These are some of the things I would try, if my Superior drums where doing what you are describing.
CJ