(I realize that, moved from another topic, my previous message lost some context and is not clear anymore. Let me rephrase.)

My problem: the mediaplayer can't play anything (audio video, radio) nor I can change its internal volume. These operations fail and I get the following error message (translated from french) "impossible to process operation".

Facts in chronological order:

• This n900 has been flashed a few days ago.
• The mediaplayer used to worked like a charm (local or upnp mp3 & videos).
• After spending an evening using the mediaplayer, on the day after, I found it broken.
• All of my previous n900 devices had this same issue at some point and I still can't identify why.
• openmediaplayer suffers of the exact same problems (an was working good when mediaplayer was working too).

Investigations:
The mediaplayer is so opaque to me (no parameters, useless log in /tmp/, etc.) that I couldn't find out a solution by myself (I often do). I even can't understand why this is the only app I can't run from the shell: my idea was to run it with strace (gathered from Debian Squeeze armel repo) to see on which system call the program may be trapped or could throw any internal error (strace makes it very verbose, we can see printf calls, etc.). (I mean I can run it, but it does show up!)
I've also tried a lot of other things of course: restarting trackerd, killing mafw-* processes, reboot, inspecting log file (into /tmp/ ), etc. without any success.
I suspect a possible communication issue between mediaplayer and dbus (it uses it right?) to run underlying players and volume control. To me, it's like they can't talk anymore. I may be totally wrong, but the rest of the mediaplayer works (browing files, upnp shares, etc.).

Thank you for reading!
--
PS: my firmware is 20.2010.36-2 and packages are up to date.