cleanup causes permission problems

After a cleanup I loose permissions (f.e. SELECT, MODIFY). When I listed the system_auth/permissions CF after cleanup I recognized, around the half of all permissions lost - BUT: If I list the permissions table with consistency ALL, all entries appear again and my programm continues working. Only if I manual trigger that read-repair! That tells me indirect, that system_auth is reading using consistency ONE, what causes problems after cleanup . A good approach could be to re-read system_auth after permission fail with consistency > ONE to trigger read-repair once and keep speed.