Im trying to setup carddav with posteo. I am currently using Version 1.5.2 (also tried 1.5.3) and contacts sync but it takes a long time (more than 10 min) to perform the first initial sync of ~250 contacts.
Additionally, there is no feedback at all on the number of synced (or missing) contacts, i.e. I do not know how many contacts still need to be synced.
On a first try, ~50 of the 250 contacts are synced to the device than the sync is ended.
Version 1.5.2 is better than 1.5.3 but also is not able to sync the contacts in one batch.
Can I help you debug this problem?