LDAP and Clients seems not working

[kromonos]

I've tried several apps, but after switching an account to LDAP auth, I can login via WebUI, but not anymore via App. Is it possible, that the API does not check LDAP auth?
I'm using SubSonic 5.2.1 (build 4428) incl. Premium Subscription.

EDIT: OK, seems so, Subsonic forgott my login and seems not be able to refetch data from LDAP. Sometimes it works, but after some time, normaly 10 to 15 minutes, it isn't possible to login anymore. After restarting Subsonic, it's working again for 10 up to 15 minutes ...

EDIT2:
[2015-05-31 15:05:12,574] INFO SubsonicLdapBindAuthenticator - User 'kromonos' successfully authenticated in LDAP. DN: CN=kromonos,cn=Users,dc=pdc,dc=kromonos,dc=net
[...]
[2015-05-31 15:25:16,024] INFO RESTRequestParameterProcessingFilter - Authentication failed for user kromonos

Between this 2 logins I changed nothing at the subsonic and LDAP (Samba4 AD DC) server

EDIT3:
OK. Got it. After exporting my playlists an deleting account at my subsonic server, LDAP Bind auth creates his own user. with this, it seems to work. So I imported my playlists again and hope, the error is gone.
Also login from Apps is working without any problem