Sound problems in 8.04 with Amarok and other programs (multiple sound outputs but only one playing)

[Loïc Martin]

Hi,

Since 8.04 (install from scatch) I can't have both Amarok playing and 
still hear sound from another program (f.e. Firefox 3 playing a flash 
video), and if a seconf user was watching a Youtube video in Firefox, 
even if it's on pause I can't output any sound from my session.

Does anybody knows if there's a howto somewhere about solving these 
issues, or if there's a simple way to address the mess?

Thanks in advance,
Loïc