Time Machine on OXS X 10.9.5 to sparse bundle on LAN. While doing the backup and when the progress bar is at the point of approx 80% it gets stuck for more minutes (3 to 5 minutes). In other regions the bar makes, even if slightly, small but clear visible progress steps. Is this a known phenomenon? What are possible reasons? How to fix? "Verify backup" is made prior to every backup run and follows such. Compacting the sparse bundle was made recently too. No help.