need to reinstall pulseaudio every day

[Pierre Frenkiel <pierre.frenkiel@gmail.com>]

hi,
the problem is exactly what says my subject.
every morning, ls /usr/bin/pulseaudio gives:
    ls: cannot access '/usr/bin/pulseaudio': No such file or directory
and I must issue "aptitude reinstall pulseaudio" 
I plan to put the ls command every minute to find when it disappears,
unless somebody can give me an axplanation (and a fix...)

best regards,
--
Pierre Frenkiel