Sometimes Skype freezes silently under Ubuntu and displays that the user is still online, but actually he isn’t. From what I have read on some geek blogs, this is a permission problom.
To fix this Skype problem, remove the read permissions from some files associated with libpulse:
$ cd /usr/lib32
$ sudo chmod a-r libpulse* libpulse-simple* libpulsecommon*
I have put the asterisk * wildcard after the names, because the librepulse, librepulse-simple and librepulsecommon versions may vary from system to system.
Example 1: libpulse.so.0.13.4 libpulse-simple.so.0.0.3 libpulsecommon-1.0.so
Example 2:libpulse.so.0.12.3 libpulse-simple.so.0.0.3 libpulsecommon-0.9.22.so