Backup stuck at 50% without error message

[besendorf]

Today I tried to make a backup using D2D mode of all my Apps to a flash drive. The progress stopped at 50% and stayed there for a few hours. When my battery was almost empty (I don't have a usb adapter that allows for simultaneous charging) I unplugged the flash drive. After that the notification still showed 50%. Heres the log: seedvault-14-3.3-1729085493998.txt