Bug#674446:

[Volodymyr Shcherbyna <volodymyr@shcherbyna.com>]

I also noticed that when I have this problem I hear a click of my harddrive. 

I have three of them, and since only one is used I presume the two others go to sleep. So, when they sleep and I open my dropbox I hear a click sound like one of the sleeping disk is waking up and this transition from sleep into non-sleep is causing the dolphin to hung.

-- 
with best regards, Volodymyr.