Eric, please make a note of the below defect that could probably the reason behind this issue. You can try restarting CCX Engine (in after hours) and see if that resolves the issue. In case, you are running one of the affected versions then you can try to upgrade the latest version i.e. 10.6(1) SU2 for permanent fix.
https://bst.cloudapps.cisco.com/bugsearch/bug/CSCuq61192/?reffering_site=dumpcr
Regards
Deepak